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PROBLEMS,  PROJECTS,  AND  EXPERIMENTS 

IN  BIOLOGY 


ATWOOD 


BY  THE  SAME  AUTHOR 

CIVIC  AND  ECONOMIC 
BIOLOGY 

"This  latest  addition  to  civic  biology  offers  a  new 
viewpoint  in  science  teaching,  and  in  giving  prom- 
inence to  the  practical  phases  of  the  science" — 
General  Science  Quarterly  (Mass.) 


COMPARATIVE   VERTEBRATE 
DISSECTION 

This  volume  is  the  result  of  many  requests  from 
teachers  for  a  manual  "different"  from  those  now  in 
use.  The  book  prepares  the  student  for  a  continua- 
tion of  the  study  to  its  logical  conclusion  in  uni- 
versity courses. 

P.  BLAKISTON'S  SON  &  CO. 

PHILADELPHIA 


PROBLEMS,  PROJECTS, 

AND 

EXPERIMENTS  IN  BIOLOGY 


BY 

WM.  H.  ATWOOD,  M.  A.,  M.  S. 

MILWAUKEE   STATE  NORMAL   SCHOOL 


55  ILLUSTRATIOxNS 


PHILADELPHIA 

P.   BLAKISTON'S  SON  &  CO 
1012   WALNUT   STREET 


^ 
0 


.c^ 


Copyright,  1923  by  P.  Blakistox's  Son  &  Co. 


PRINTED  IN  U.  S.  A.  . 
BY  THE  MAPLE  PRESS  YORK  PA 


n>  C.  State  Cof/eg 


FOREWORD  TO  TEACHERS  AND  STUDENTl 

The  contents  of  this  manual    are    arranged    to    correspond    In 

sequence  with  the  author's  Civic  and  Economic  Biology,  but  it  has 
been  assembled  with  the  thought  in  mind  thai  it  may  be  used  with 
other  texts.  If  copies  of  Civic  and  Economic  Biology  arc  available 
as  references,  this  manual  should  be  adapted  to  any  course  in  biology, 
either  with  or  without  a  special  text.  With  this  in  mind,  referent 
to  various  biological  works  have  been  placed  below  the  sectional 
headings.  It  is  the  author's  hope  that  the  references  cited  will  be 
available  to  the  students  in  the  laboratory. 

Laboratory  work  is  naturally  so  dependent  upon  conditions  which 
obtain,  both  within  the  laboratory  and  in  the  environment  of  tin- 
school,  that  it  is  best  to  have  a  considerable  variety  of  exercis 
suggested  from  which  selections  may  be  made.  It  is  hardly  to  be 
expected  that  all  of  the  exercises  suggested  here  will  be  worked  out, 
or  that  they  will  be  taken  up,  in  all  cases,  in  the  order  given.  They 
are  all  workable,  and  something  of  value  may  be  learned  from  each. 
Experiments  which  often  fail,  or  give  indifferent  results,  have  been 
eliminated.  Those  which  have  been  selected  should  stimulate 
thought.     A  problem  requires  thought  for  its  solution. 

Class  spirit  and  cooperation  are  stimulated  if  student  commits 
are  appointed  or  elected  to  assist  the  instructor.  Student-  should 
feel  that  they  are  as  reponsible  for  the  success  oi  the  course  as  the 
teacher.  The  membership  of  the  committee-  should  be  changed 
from  time  to  time  so  that  each  student  will  serve  in  a  variety  oi 
activities.  If  the  class  is  well  organized,  a  diversity  of  work  may 
go  on  at  one  time;  but  under  unfavorable  condition-  it  will  be  more 
necessary  to  keep  all  members  working  at  the  same  problem  at  a 
given  time. 

Variation  in  the  content  and  method  has  been  especially  sought. 
Students  soon  lose  interest  in  a  drawing  course,  or  a  laboratory 
course  in  essay  writing.  Teachers  also  enjoy  a  course  more  it  it 
can  be  made  to  varv  in   method  and   content    from  year  to  J 


'W«    J*    ) 


vi  FOREWORD    TO    TEACHERS    AND    STUDENTS 

There  should  be  a  difference  between  a  problem,  a  project,  and  an 
experiment;  but  the  difference  is  more  in  the  point  of  view  of  the 
student  and  teacher  than  in  the  exercise  itself.  Do  not  make 
experiments  of  mere  demonstrations.  It  is  not  necessary  that  all 
things  be  taught  by  the  problem  method.  Simple  things  should  be 
simply  taught. 

The  directions  are  stated  very  briefly.  The  student  should 
be  given  an  opportunity  to  make  mistakes.  They  should  have  an 
educational  value.  Directions  which  are  given  in  too  great  detail 
eliminate  opportunity  for  initiative.  Students  should  ask  few 
questions  of  the  teacher  and  should  solve  their  own  problems. 

Quizzes  should  be  frequent  and  should  cover  all  reports,  topics, 
demonstrations,  field  trips,  etc.  A  quiz  is  a  review.  Everything 
should  be  reviewed.  Students  are  responsible  in  the  quiz  for  the 
projects  of  others  which  have  been  presented  to  the  class.  Experi- 
ence has  shown  that  students  study  better  if  quizzes  are  frequent  and 
searching.  Written  work  should  be  handed  in  daily,  as  it  is  ready, 
and  that  which  fails  to  equal  the  standard  of  the  course  should  be 
rewritten.  Teachers  and  committees  should  return  students' 
papers  promptly. 

Advance  preparation  should  be  made  for  many  laboratory 
problems  and  projects.  Look  ahead  in  the  manual  and  make 
arrangements  for  such  exercises.  Seedlings  require  from  two  to 
three  weeks  to  sprout  and  start  their  growth.  Paramecia  cultures 
should  be  started  about  two  weeks  before  they  are  to  be  used.  Some 
materials  which  can  be  collected  in  the  fall  for  winter  use  should  be 
carefully  preserved.  Reports  and  topics  should  be  assigned  in 
advance  and  should  be  ready  when  the  study  with  wrhich  they  are 
connected  is  before  the  class. 

The  illustrations  have  been  selected  with  great  care  as  to  their 
teaching  value  and  also  for  their  scientific  accuracy  and  artistic 
qualities.  Good  illustrations  are  a  stimulus  to  the  student.  Those 
which  have  been  borrowed  are  credited  in  the  legends. 

It  is  the  hope  of  the  author  that  the  use  of  this  manual  will  ensure 
both  enjoyment  and  efficiency  to  the  courses  in  the  biological  sciences 
where  it  is  used. 

Wm.  H.  At  wood. 


TABLE  OF  CONTENTS 

Pace 
i    ORGANIZATION , 

2    INORGANIC  MATTER 2 

3.  CHARACTERISTICS  OF  LIVING  MATTER 

4.  ENVIRONMENT  AND  ADAPTATION 4 

5.  THE  GOLDENROD,  A  TYPICAL  PLANT 

6.  INSECT  STUDY 6 

7.  THE  CRAYFISH  (CRAWFISH) id 

8.  WORK  WITH  ROOTS  AND  SOILS 14 

9.  PLANT  STEMS  AND  FORESTRY 

10.  THE  STRUCTURE  AND  WORK  OF  LEAVES 23 

11.  FOOD  AND  ITS  USES 

12.  CHEMICAL  FOOD  TESTS 

13.  DIGESTION 36 

14.  RESPIRATION  AND  CIRCULATION 39 

15.  TROPISMS  AND  RESPONSES 41 

16.  STUDIES  OF  PROTOZOANS 45 

17.  LESSONS  WITH  ALG^,  MOSSES,  AND  FERNS 4  7 

18.  THE  LIFE  HISTORY  OF  THE  PINE  TREE 

19.  THE  PARTS  AND  FUNCTIONS  OF  THE  FLOWER 50 

20.  CELL  DIVISION 

ai.  THE  LIFE  HISTORY  OF  FLOWERING  PLANTS 

22.  FRUITS  AND  SEED  DISTRIBUTION 

23.  STUDIES  IN  PLANT  PROPAGATION 

24.  SEEDS  AND  SEED  GERMINATION 6a 

25.  LIFE  HISTORIES  OF  ANIMALS 

26.  THE  FROG 

27.  STUDIES  ON  THE  ECONOMIC  IMPORTANT  I    <>l     DOMLsri- 

CATED  ANIMALS  AND  PLANTS 

28.  VARIATION  AND  HEREDITY  AND  THEIR  APPLICATION    I 

PLANT  AND  ANIMAL  BREEDING 

29.  EUGENICS  AND  EUTHENICS 

vii 


Vlll  TABLE    OF    CONTENTS 

Page 

30.  THE  DOCTRINE  OF  EVOLUTION 78 

31.  BACTERIA,  YEASTS,  AND  MOLDS 79 

32.  BACTERIA  AND  CONTAGIOUS  DISEASES  OF   MAN 84 

33.  CONTAGIOUS  DISEASES  OF  PLANTS 87 

34.  WEEDS 88 

35.  PARASITIC  WORMS 89 

36.  INSECT  PESTS 90 

37.  RATS  AND  MICE 94 

38.  FISH  AND  POND  LIFE 95 

39.  THE  PERCH  (DISSECTION) 96 

40.  BTRDS 98 


PROBLEMS,  PROJECTS 

AND 

EXPERIMENTS  IN  BIOLOGY 

i.  ORGANIZATION 

References 

Civic  and  Economic  Biology,  Atwood,  Preface  and  Study  i. 
Civic  Biology,  Hodge  and  Dawson,  Chaps.  I  and  IT. 
Elementary  Biology,  Gruenberg,  Preface  and  Chap.  I. 
Biology  for  Beginners,  Moon,  Chap.  I. 
Hunter's  Biologies,  Preface  and  Chap.  I. 
The  Teaching  of  Biology,  Lloyd  and  Bigelovv. 
Principles  of  Science  Teaching,  Twiss,  Macmillan  Co. 
The  Teaching  Botanist,  Ganong,  Macmillan  Co. 

I.  Soon  after  the  beginning  of  the  school  year,  it  will  he  well  to 
hold  an  election  and  choose  committees  to  attend  to  the  business  of 
the  class.  The  library  committee  should  have  charge  of  tin-  books 
and  the  bookcase.  A  good  system  of  cataloguing  should  be  insti- 
tuted, and  every  book  should  always  be  in  its  place  at  the  dose  of  the 
day.  The  archives  committee  should  have  charge  of  all  paper- 
and  reports  which  are  produced  by  the  members  of  the  das  The 
museum  committee  should  have  charge  of  the  museum  cases  and 
should  see  that  all  specimens  are  kept  in  good  order.  The  committee 
in  charge  of  apparatus  should  see  that  the  equipment  which  belongs 
to  the  department  of  biology  is  conserved  and  put  away  in  ur""d 
order.  The  supplies  committee  should  purchase  for  the  instructor 
such  materials  as  are  to  be  bought  locally  and  should  keep  the 
materials  used  in  the  course  in  good  order.  The  committee  on 
ventilation  and  sanitation  should  assist  the  instructor  in  such  matters 
as  lighting,  fresh  air,  heating,  cleanliness,  etc.  There  should  he  Min- 
or more  committees  in  charge  of  the  plants  and  animals  which  a 
kept  alive  in  the  department.  Are  there  any  other  commitl 
which  should  be  appointed?  Remember  that  Loyalty  t<>  duty  and 
a  wholesome  spirit  of  cooperation  are  the  prime  essentials  which 

i 


2  PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 

make  for  a  successful  course  in  biology.     The  class  expects  every 
one  to  do  his  duty  promptly. 

2.  INORGANIC  MATTER 

References 

Civic  and  Economic  Biology,  Atvvood,  Study  i. 
Introductory  chapters  of  other  biologies. 

2.  Exhibit  of  Kinds  of  Matter.— The  supplies  committee  should 
arrange  an  exhibit  of  chemical  elements,  chemical  compounds,  and 
minerals.  Place  them  in  three  groups  and  label  each  specimen. 
Make  such  remarks  to  the  class  as  may  seem  appropriate,  and  have 
the  names  of  the  specimens  learned  by  the  students. 

Prepare  another  similar  exhibit  of  carbohydrates,  fats,  and  proteins. 
Understand  that  the  chemical  composition  of  living  things  and 
their  products  is  much  more  complex  than  that  of  minerals. 

3.  Crystallization. — Heat  about  a  half  cupful  of  water  to  boiling 
and  add  as  much  copper  sulphate  as  will  dissolve  in  the  boiling  water. 
Pour  the  liquid  into  a  dish  and  let  it  cool.  Watch  the  formation  of 
crystals  of  copper  sulphate. 

Dissolve  some  more  copper  sulphate  in  warm  water  and  put 
it  away  to  evaporate  slowly.  The  crystals  which  form  in  this  way 
should  be  larger.  Why?  Try  to  get  crystals  of  the  following  by 
this  method:  ammonium  nitrate,  sugar,  salt,  glucose,  starch,  glue, 
potassium  sulphate,  potassium  chlorate,  and  potassium  dichromate. 
Each  student  should  not  try  all  of  the  above  mentioned  materials, 
but  if  each  takes  one,  results  may  be  compared.  Do  they  all  form 
crystals?     Are  the  crystals  of  each  salt  alike? 

4.  Draw  diagrams  of  some  of  the  crystals. 

5.  Irritability. — Pour  a  small  amount  of  a  solution  of  silver  nitrate 
into  each  of  four  test  tubes.  To  the  first  add  some  sodium  chloride 
solution.  To  the  second  add  some  sodium  bromide  solution.  To 
the  third  add  some  sodium  iodide  solution,  and  leave  the  fourth  as  it 
is.  Place  them  in  the  sunlight.  How  long  does  it  take  to  change 
the  color? 

6.  Report. — Some  student  may  prepare  a  topic  on  the  subject, 
The  Chemical  Changes  Produced  by  Light  on  Silver  Salts.  See  a 
chemistry,  or  a  book  on  photography. 


CHARACTERISTICS   OF   LIVING    MATTER 


3.  CHARACTERISTICS  OF  LIVING  MATTER 
See  the  same  references  as  in  the  preceding  se<  tion. 

7.  Growth. — Committees  or  individuals  may  study  some  of  the 
following  phenomena  of  growth  and  report  to  the  clas 

How  rapidly  do  leaves  come  out  of  the  hud?  In  what  ways  are 
various  leaves  and  flowers  folded  in  buds?  Do  stems  grow  in 
length  after  they  are  once  ^_^___„_____ 
formed?  How  do  they  in-  iff 
crease  their  diameters,  by 
adding  to  the  outside  or 
throughout  the  entire  stem? 
Do  leaves  reach  a  certain  size 
and  then  stop  growing?  Is 
the  color  of  young  leaves 
lighter  or  darker  than  old 
ones?  Which  plants  grow 
the  more  rapidly,  vines  or 
plants  with  heavy  stems? 

8.  Plant  some  seeds  and 
note  the  growth  of  the  roots. 
Do  they  increase  in  diameter? 
Do  they  grow  only  at  the  tips, 
or  throughout  their  entire 
length?  In  a  young  seedling, 
are  the  roots  or  the  leaves  the 
more  extensive? 

9.  How  long  does  it  take 
the  following  animals  to  be- 
come fully  grown:  fly,  potato 
beetle,  snake,  turtle,  cow,  sheep,  dog,  chicken,  robin,  man,  elephant  'J 
How  long  does  it  take  the  eggs  of  the  following  bird-  to  hate  li :  robin. 
chicken,  duck? 

Compare  the  proportions  of  the  parts  of  a  young  dog  with  those 
an  old  one.     How  do  they  change  as  the  puppy  becomes  a  dog? 

10.  Irritability. — If  a  specimen  of  Mimosa  is  growing  in  the  labora- 
tory, touch  its  leaves  and  note  how  they  respond.     It  no  plant  is 


Fig.  1. —  Diagram  of  a  chamber  to 

phototn>i>ism.     {Fundamental 
Gager.) 


4  PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 

available,  plant  some  seeds  and  have  one  ready  for  observation 
later. 

Place  a  young,  rapidly  growing  weed,  or  some  other  plant,  in  a 
dark  box  with  light  admitted  through  only  one  side.  After  a  few 
davs  note  its  response  to  light.  Observe  the  leaves  of  the  plants  in 
the  windows  and  other  places.  How  are  their  leaves  arranged  in 
reference  to  the  light? 

Can  a  committee  find  a  compass  plant  and  bring  it  into  the  labora- 
tory as  an  exhibit.     Explain  to  the  class  just  how  it  grew. 

Let  a  committee  experiment  with  earthworms  to  find  if  they 
respond  to  light.  Do  they  respond  to  a  jar?  To  sound?  Touch 
one  with  a  drop  of  water,  then  with  salt  water,  then  with  a  weak  acid. 
Compare  results.  Touch  first  the  head  and  then  the  tail  with  a 
toothpick  and  determine  which  end  is  the  more  sensitive.  Place 
one  on  a  moist  blotter  on  a  dry  board.  Will  it  crawl  off  of  the  blot- 
ter? Is  it  sensitive  to  dry  surfaces?  Report  all  of  these  results  to 
the  class.  Some  of  them  may  be  repeated  in  the  presence  of  the 
class. 

Other  experiments  on  the  responses  of  plants  and  animals  will 
be  performed  later  in  the  course. 

4.  ENVIRONMENT  AND  ADAPTATION 

References 

Civic  and  Economic  Biology,  Atwood,  Studies  2,  3,  and  4. 
Civic  Biology,  Hunter,  Chaps.  II  and  III. 

11.  Field  Trip. — The  class  should  be  divided  into  troops  of  three 
to  six  students  each  for  the  study  of  the  various  features  of  the 
environment  in  the  vicinity  of  the  school.  One  group  may  study  a 
meadow,  another  a  brook,  another  a  pond,  and  another  a  woods. 
Make  out  a  plan  of  what  you  expect  to  study  before  you  start. 
Never  go  on  a  field  trip  without  a  notebook.  Keep  a  record  of  what 
you  find.  Note  the  conditions  of  light,  heat,  moisture,  abundance 
of  plants  and  animals,  soil,  and  the  kinds  of  life  found  in  each  region. 
Bring  samples  and  specimens  to  the  laboratory  for  exhibition  and 
discussion  on  the  day  following  the  excursion.     Write  lists  on  the 


THE   GOLDENROD  - 

board  of  the  kinds  of  plants  and  animals  found  in  ea<  li  lo(  alii  y  and 
compare. 

Do  not  wear  your  best  clothing  on  field  trips.     I  sped  to  gel  your 

feet  muddy.     Those  who  visit  a  pond  or  brook  should  ha 
to  secure  the  small  animals  which  live  there.     Water-tight  \ 
should  be  provided  to  bring  home  the  catch.     Bags  and   baskets 
will  be  convenient. 

12.  Project— Let  each  student  of  the  class  choose  a   plant   or 
animal  and  make  a  special  study  of  its  relation  to  temperature,  water. 
light,  air,  soil,  food,  and  shelter.     The  results  should   be  written 
up  and  filed   with   the  archives  committee.     Sonic   of   the-   m< 
interesting  ones  should  be  read  to  the  class. 

5.  THE  GOLDENROD,  A  TYPICAL  PLANT 

References 

Civic  and  Economic  Biology,  Atwood,  Study  5  and  Fig.  1  76. 
Wild  Flowers,  Blanchan,  Doubleday,  Page  &  Co. 

13.  Field  Trip. — Read  Study  5  in  Atwood 's  Biology,  and  make 
arrangements  to  go  on  a  field  trip  to  study  the  goldenrod  or  some 
other  typical  plant. 

Where  do  they  grow?  What  kind  of  soil?  What  arc  tin-  light 
and  moisture  conditions  of  their  habitat?  What  other  plant-  urrow 
with  them?  Are  they  more  or  less  vigorous  than  their  competitoi 
Are  they  more  or  less  numerous  than  all  of  the  other  kind-  iA  plants 
in  their  vicinity?  How  do  they  compare  in  this  respect  with  any 
one  kind?  How  do  they  rank  in  abundance  as  compared  with  each 
of  the  other  kinds  of  plants  growing  with  them? 

How  tall  is  the  highest  plant  which  you  can  find?  What  gave  it 
this  advantage?  Does  it  bear  more  seeds  than  the  othei  What  is 
the  average  height  of  goldcnrods?  Compare  them  with  other  plants 
in  their  environment  in  this  respect. 

Note  the  color  of  the  flowers.  Estimate  the  Dumber  ^\  individual 
blossoms  in  a  large  and  an  average  sized  flower  cluster.  1  some  have 
gone  to  seed,  count  the  number  of  seeds  to  a  flower  and  to  a  duster. 
Scatter  some  seeds  in  the  wind  and  watch  them  -ail.      !»«•  they  sail 


6  PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 

as  well  as  the  dandelion  seeds?  What  is  the  advantage  in  having  the 
blossoms  in  a  cluster? 

Note  how  tall  the  stems  are.  Are  they  branched?  Why  would 
it  be  poor  economy  to  have  them  branched  at  the  bottom? 

How  are  the  leaves  arranged  on  the  stem?  Where  are  the  ones 
which  are  dying?  Why  do  they  die  first?  Note  the  shape  of  the 
leaves.  Does  each  get  relatively  more  light  than  it  would  if  they  were 
broad  and  large?     Does  this  same  principle  hold  for  blades  of  grass? 

Find  a  plant  which  is  growing  in  loose  soil  and  dig  it  up.  Find  its 
underground  stems  and  its  roots.  What  is  the  color  of  each?  Are 
there  any  scales  on  the  stems?  What  are  the  scales  morpholog- 
ically? Do  you  think  much  food  could  be  stored  underground? 
How  many  plants  would  have  grown  from  the  one  which  you  dug  out 
the  next  spring?     What  is  the  use  of  the  underground  stem? 

Capture  as  many  of  the  various  insects  inhabiting  the  goldenrod 
as  you  can.  There  will  be  beetles,  bees,  flies,  and  butterflies. 
Assign  them  to  one  of  these  groups.  Have  a  separate  receptacle 
for  each  group  and  take  them  to  the  laboratory  where  students  may 
find  what  their  names  are  as  a  project.  What  were  the  insects  doing 
on  the  goldenrod?     Are  any  of  them  of  any  benefit  to  the  plant? 

Bring  some  goldenrod  and  other  plants  to  the  class-room  for 
reference  during  the  quiz  which  follows  the  field  trip. 


6.  INSECT  STUDY 

References 

College  Zoology,  Hegner,  Macmillan  &  Co. 

General  Zoology,  Pearse,  Henry  Holt  &  Co. 

Civic  and  Economic  Biology,  Atwood,  Studies  6,  64,  65,  and  66. 

14.  Laboratory  Work.- -The  grasshopper  is  the  largest  of  the 
common  insects,  and  it  is  of  a  generalized  type  of  structure.  These 
facts,  together  with  its  abundance,  make  it  a  favorite  for  laboratory 
study  as  a  typical  insect.  If  the  natural  history  of  the  insect  is  to 
be  studied,  the  bee  is  considered  superior.  See  Atwood's  Biology, 
Study  6,  also  pp.  411  and  412.  Large  lubber  grasshoppers  may  be 
had  from  the  dealers,  or  smaller  ones  may  be  caught  locally. 


INSEC1    STUDY 

Make  a  sketch  of  the  side  view  of  the  grasshopper  to  show  the 

features  mentioned  below.     The  body  of  an  insect  is  divided  into 
three  divisions —the  head,  thorax,  and  abdomen,     bind  the  lai 
compound  eyes.     Examine  them   with   a   lens   to  the   facet 

Can  the  grasshopper  see  in  all  directions  at  one  time  withoul  movi 
his  head?     The  three  simple  eyes  will  be  seen  with  the  aid  of  a  lei 
One  is  in  the  middle  of  the  face,  and  another  before  ea<  h  compound 
eye.     They  appear  as  small  beads. 

The  antennae  are  possessed  of  how  many  joints     How  great  is 
their  range  of  movement? 


Wd 


^ 


ATAX 


obd 





omen 


•  compound  e^e 
ocellus     |  /pronotum  j  auditory  or^an 


"tarsus 


Fig.  2. — External  view  of  a  grasshopper  to  show  its  parts.        [ftet    WaU 
Connecticut  Geological  and  Natural  History  Survey.  Bulletin  No.   '■ 


The  mouth  parts  are  shown  here  and  in  Figs.  328  and  329  in 
Atwood's  Biology.  Find  them  in  your  specimen  and  learn  the 
names  of  their  parts.  They  may  be  arranged  as  in  Fig,  329  and 
drawn. 

The  thorax  is  composed  of  three  parts  (somites  The  first  i> 
called  the  collar.  It  is  movable  on  the  body.  Note  that  it 
bears  the  first  pair  of  legs.  The  second  division  bears  a  pair  of  wings 
and  a  pair  of  legs  as  does  the  third.  The  divisions  ,,|'  the  thorax 
are  called  the  prothorax,  mesothorax,  and  metathorax. 


8 


PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 


Compare  the  two  pairs  of  wings.  Which  pair  does  the 
most  of  the  flying?  How  does  the  grasshopper  make  its  sounds? 
Do  you  know  how  the  katydid,  cricket,  and  cicada  make  their 
sounds? 

Study  the  leg  of  an  insect.  The  first  two  parts  are  small  and 
difficult   to  make  out.     They  are  the  coxa  and  trochanter.     The 

femur  is  the  largest  part  of  the  leg.  It  is  followed 
by  the  slender  tibia,  and  the  foot  is  the  tarsus. 
Compare  the  legs  of  the  grasshopper  with  those 
of  other  insects. 

Draw  an  insects'  leg  and  label  the  parts. 
The  abdomen   is   composed  of  rings  (somites). 
How   many   are  there?     The  first  ring  is  incom- 
plete below  in  the  grasshopper  and  contains  the 
ear.     See  Fig.  121  in  Atwood's  Biology. 

15.  Report. — How  does  the  ear  of  the  grass- 
hopper work? 

If  a  live  specimen  is  available,  its  respiration 
should  be  observed.  The  abdomen  will  be  seen  to 
swell  and  contract  as  air  is  taken  into  the  tracheal 
system  and  let  out  again.  See  Figs.  33  and  96  in 
Atwood's  Biology.  Count  the  spiracles  along 
each  side  of  the  abdomen.  You  should  be  able 
to  find-  two  on  each  side  of  the  thorax  also.  An 
ovopositor  consisting  of  two  or  more  spines  is 
usually  found  at  the  end  of  the  abdomen  of  female 
insects. 

16.  Report. — How    do    grasshoppers   lay    their 


Fig.  3. — Mouth 
parts  of  a  grass- 
hopper, m,  Man- 
dible; max,  max- 
illa; L,  labium;  p, 
palps.  (Elements 
of  Animal  Biology, 
Holmes.) 


eggs 


17.  If  it  is  desired  to  study  the  internal  anatomy  of  an  insect,  a 
committee  may  be  asked  to  find  suitable  directions  in  a  manual  and 
copy  them  on  the  board. 

18.  Exhibit. — The  museum  committee  may  prepare  an  exhibit 
to  show  one  or  more  insects  of  each  of  the  common  orders  of  the  class 
Insecta.  Notes  which  state  the  differences  which  distinguish  the 
orders  may  be  made  to  accompany  the  exhibit.  The  notations  will 
be  somewhat  like  the  following  table: 


[NSECT    STUDY 


Fig.  4. — The  internal  anatomy  of  the  grasshopper.     The  regions  of  th 
are:  hd,    Head;   th,    thorax;   and   ab,   abdomen.     The   regions   of   tin- 
tract   are:      tn,    Mouth;   oe,   esophagus;   p,   pouch;   g,  gizzard;    1 
s,  stomach;  i,  ileum;  c,  colon;  and  r,  rectum.     Other  parts  arc:  .;.   Anteni 
b,   brain;   ce,   cement  gland;   d,   duct  of  salivary  glands;   t,   ex  tubuli 

h,  heart;  o,  oviduct;  ov,  ovaries;  sg,  salivary  glands;  vg,  ventral  ganglia  of  m 
system;  w,  wall  of  body.      (Elementary  Zoology,  Galloway.) 


Fig.  5. — Cross  section  of  the  body  of  the 
ap,  First  joint  of  leg;  bw,  body-wall  which  is  made  up 
muscles;  c,  gastric  caeca;  /*.  heart;  /.    pa  1  ;  of  body-cavity;  ph. 
1-3,   tracheal  tubes;   sg,   salivary  gland  ventral   | 

mentary  Zoology,  Galloway.) 


IO  PROJECTS   AND   EXPERIMENTS   IN  BIOLOGY 

Aptera :  >il\  ir  fish;  no  wings,  body  covered  with  scales. 

Ephemerida:  May-flies;  delicate  four  winged  flies,  two  or  three    setae  project 

from  the  end  of  the  body. 
Odonata:  dragon-flies  and  damsel-flies;  four  winged,  long  bodied  insects. 
Orthoptera:   grasshoppers,    crickets,    roaches,    katydids,    walking-sticks,    and 

mantids;  chewing  mouth  parts,  straight  wings. 
Hemiptera:  bugs,  cicadas,  scale  insects;  piercing  mouth  parts. 
Lepidoptera  :  butterflies  and  moths;  large  scaly  wings. 
Diptera:  flies  and  mosquitoes;  only  one  pair  of  wings. 

Hymenoptera:  ants,  bees,  wasps,  and  ichneumon-flies;  wings  hooked  together. 
The  best  reference  for  this  work  is  General  Zoology,  Pearse,  Henry  Holt  and  Co. 


7.  THE  CRAYFISH  (CRAWFISH) 

References 

Civic  and  Economic  Biology,  Atwood,  pp.  30,  13S,  and  142. 

General  Zoology,  Linville  and  Kelly,  Ginn  &  Cc. 

Practical  Zoology,  Hegner,  Macmillan  Co. 

Biology  for  Beginners,  Moon,  Chap.  XXII. 

Civic  Biology,  Hodge  and  Dawson,  Chap.  XXVI. 

New  Essentials  of  Biology,  Hunter,  Chap.  XVIII. 

The  laboratory  work  on  the  crayfish  is  given  at  this  place  in  the  manual,  but 
the  needs  of  the  course  may  require  that  it  be  studied  elsewhere.  No  large 
amount  of  space  was  given  to  this  form  in  Atwood 's  Biology  because  it  can  be 
studied  satisfactorily  in  the  laboratory,  and  it  is  of  little  economic  and  civic 
value.     Ho  vever,  it  has  long  been  a  favorite  for  laboratory  dissection. 

Crayfish  may  be  taken  from  the  ponds  and  brooks  where  they  live  by  fastening 
a  piece  of  fat  meat  on  the  end  of  a  string  and  casting  it  into  the  water.  When  the 
animal  seizes  the  meat,  it  may  be  drawn  from  the  water  before  it  has  time  to 
"think  it  over"  and  let  loose  of  the  bait.  They  may  be  had,  alive  or  preserved, 
from  the  dealers.     The  lobster  is  better  for  dissection,  because  it    is  larger. 

19.  The  live  crayfish  may  be  kept  in  shallow  water  in  the  labora- 
tory indefinitely.  They  should  be  fed  pieces  of  meat  and  bread. 
Why  must  they  be  kept  in  shallow  water?  Must  they  be  allowed  an 
opportunity  to  come  to  the  surface?  Why  do  they  come  to  the 
surface?  How  do  they  seize  their  food?  How  is  it  held  while  it  is 
being  eaten?  How  does  the  crayfish  walk?  Which  legs  push  and 
which  pull?  Are  the  pinchers  used  in  walking?  How  many  legs  are 
there?     Do  they  all  have  claws  on  their  ends?     Compare  the  legs 


THE    CRAYFISH  j  , 

with  those  of  the  grasshopper.     Note  how  the  feelers  are  used.     How 

many  are  there?  The  smaller  ones  arc  called  antennules,  and  the 
larger  are  called  antennae.  Find  the  eyes.  Can  they  be  moved? 
Find  the  large  fin-like  structure  at  the  end  of  the  tail.  Thro* 
crayfish  in  a  vessel  of  deep  water  and  learn  how  it  swims.  I  >es4  ribe 
the  process.  Does  the  crayfish  prefer  to  hide  under  something  oc 
to  remain  out  in  the  open?  Take  one  out  of  the  water  and  pla<  e  it 
on  the  desk.  How  does  it  retreat?  How  docs  it  make  a  defei 
when  retreat  is  not  possible?  With  a  piece  of  glass  tubing  fon  e  some 
red  ink  or  other  colored  solution  into  the  water  near  the  head  of 
the  crayfish.  Note  by  this  how  the  water  circulates  through  the  gill 
chambers  on  the  sides  of  the  body.  Watch  the  swirnrnerets  in  their 
rhythmical  movements  under  the  abdomen  (tail). 

The  dead  crayfish  will  be  colored  red  if  it  is  preserved  in  formalin. 
What  are  the  natural  colors  of  crayfish?  Are  they  all  of  the  same 
color?     Are  their  colors  protective? 

Note  the  two  body  divisions  in  the  dead  specimen.  The  head 
and  thorax  are  combined  in  one  piece,  called  the  cephalothorax. 
The  part  commonly  called  the  tail  is  the  abdomen.  The  mouth 
parts  are  more  numerous  than  in  the  insects.  The  first  pair  are 
hard  and  are  called  the  mandibles.  The  second  and  third  pair  art- 
called  the  first  and  second  maxillae  respectively.  The  three  pairs 
which  follow  are  called  maxillipeds.  There  are.  then.  >i\  pair-  of 
appendages  which  have  to  do  with  eating,  but  the  posterior  pair-  are 
not  of  so  much  importance  as  the  anterior  on<  Tin-  posterior 
pairs  also  help  in  passing  water  over  the  urill<.  Remove  the  mouth 
parts  and  place  them  in  a  series  on  a  sheet  of  paper.  When  they 
are  arranged  have  them  inspected.  It  they  are  all  perfect,  th< 
should  be  drawn  and  labeled.  Not  all  students  will  succeed  in  get- 
ting all  of  the  parts  out  entire.  They  should  be  removed  with  the 
greatest  care  with  sharp  pointed  tweezers. 

Draw  a  cheliped,  a  leg,  a  swimmeret,  ami  the  telson. 

The  crayfish  is  a  somited  animal.     Count  the  rings  in  theabdonu 
The  telson   may  or  may  not   be  counted,  a-  you  like.     Are  then- 
evidences  of  segmentation  in  the  cephalothonu 

Dissect  the  animal  by  opening  the  -hell  (carapace-  on  the  back 
and  cutting  it  away.     The  stomach  is  a  lame  sac  in  the  head  end 


1  2 


PROJECTS    AND    EXPERIMENTS    IN   BIOLOGY 


the  body.  Cut  it  open  and  find  the  "teeth"  which  it  contains. 
What  are  they  used  for?  Just  back  of  the  stomach  is  the  heart. 
It  is  a  mere  sac  with  muscular  walls.  On  the  sides  of  the  stomach 
and  heart  are  the  reproductive  organs.  Nearer  the  legs  and  also 
on  the  sides  of  the  stomach  are  the  halves  of  the  pancreas.  This  is 
a  large  glandular  organ  which  secretes  digestive  juices.  The  green 
glands  are  situated  below  the  stomach  on  either  side  of  the  head. 
I  The  glands  are  not  always  green.)  They  are  excretory  and  dis- 
charge their  fluid  through  openings  in  the  bases  of  the  antennae. 
Trace  the  intestine  through  the  abdomen  and  note  the  strong  muscles 
through  which  it  runs. 


Fk;.  6. — Internal  anatomy  of  the  crayfish,  a1,  a2,  Antennae;  br,  brain;  d.l., 
duct  of  liver  or  pancreas;  e,  eye;  g,  green  gland  with  opening  at  g1;  h,  heart; 
/,  intestine;  I,  liver;  m,  mouth;  ms,  muscles;  p,  pericardium;  r,  rostrum;  s,  stom- 
ach; sa,  sternal  artery;  v.n.,  ventral  nerve  cord.      {From  Hatschek  and  Cori.) 


Draw  a  diagram  of  the  internal  anatomy  of  the  crayfish.  Make 
the  drawing  very  light  at  first  and  have  it  inspected  before  finishing 
it.  Label  it  completely.  It  is  sometimes  advisable  for  students 
who  have  had  little  experience  in  drawing  to  use  a  stencil  or  some 
other  device  to  get  a  perfect  outline  of  the  body  in  which  to  draw  the 
visceral  organs. 

The  blood  vessels  need  not  be  looked  for  unless  the  specimens  have 
been  injected.  The  nervous  system  will  be  found  by  removing  the 
other  structures  in  the  cavity  of  the  body  and  looking  first  in  the 
head  between  the  eyes  where  the  brain  may  be  seen.  What  is  its 
color  and  shape?  Show  it  to  the  instructor.  Commissures  run 
back  from  it  to  the  ventral  ganglia  going  on  either  side  of  the  esopha- 


THE   CRAYFISH 


gus.     Carefully  dissect  the  tissues  of  the  floor  of  the  cephalothi 
and  as  you  do  so,  trace  the  nerve  cord  hack  to  the  tail.     Noti     ; 
it  is  a  double  row  of  ganglia.     Is  there  a  double  ganglion  for  ea<  h 
somite?     See  figure  95  in  Atwoods'  Biology  and  note  the  nerve  cord 

of  the  earthworm.     The  crayfish  has  the  same  tyjx 
grasshopper  and  all  other  arthropods. 


I 


Fig.   7. — Diagramatic  cross  section  through  the  thora  <;. 

Appendage;  c,  carapace;  c.f.,  flap  of  the  carapace  overhanginj 
tive  tract;  g,  gills;  h,  heart;  /,  liver  or  pan  m,  m',  muscli 

ps.  space  around  the  heart  (pericardium) ;  r,  reproductive  bodies;  ■>!,  •  I 
v.a.,  ventral  artery;  v. s.,  ventral  blood  sinus  around  the  nei  AfUt  !  :ng. 

Elementary  Zoology,  Galloway.) 

The  gills  of  the  crayfish  lie  in  a  row  along  the  sides  of  the  cephalo- 
thorax  without  the  body-cavity  bu1  within  the  cover  of  the  carapa< 
They  have  three  different  attachments  and  are  in  -< 
and  three  for  each  somite.     Can  you  determine  where  the} 
attached  and  which  somites  have  three  urills  and  which 

The  ear  of  the  crayfish  is  to  be  found  in  t  he  base  i  >l  1 1  •■  nnule 

of  each  side.     It  is  shown  in  V'\^.   [ig  of  Atwood'     B  and  i-> 

more  properly  called  a  statocyst.     Why?     Cut  it  open  and  examii 
the  interior.      The   pit  lure   was   made   from    the   lobster.      U 
differ  from  the  statocyst  of  the  crayfish? 


14 


PROJECTS   AND    EXPERIMENTS    IN  BIOLOGY 


20.  Project.- -Try  to  keep  some  crayfish  alive  in  the  laboratory. 
They  should  be  in  charge  of  a  student  or  committee,  and  should  be 
ivd  twice  a  week  or  oftener.  Do  not  permit  stale  food  to  remain  in 
their  water.     Provide  something  for  them  to  hide  under. 


8.  WORK  WITH  ROOTS  AND  SOILS 

Reference 

Civic  and  Economic  Biology,  Atwood,  Studies  7  and  8. 

21.  Supplies  Committee  Project. — Secure  samples  of  various 
kinds  of  roots  to  show  to  the  class.  Try  to  get  brace  roots  of  corn; 
aerial  roots  of  ivy;  tap  roots  of  weeds,  turnip,  radish,  carrot,  beet, 
parsnip,  alfalfa;  fascicled  roots  of  dahlia,  and  sweet  potato;  and 


j>\ar 
vascular 


-smaii-ceiiea 
parenchyma 

large-celled 
parenchyma 

-nng  of  growth 

Fig.  8. — Diagramatic  cross  section  of  beet.      {Botany  of  Crop  Plants,  Robbins.) 

fibrous  roots  of  various  grasses  and  grains.  As  each  specimen  is 
presented  to  the  class  such  points  of  interest  as  are  known  may  be 
mentioned.     Drawings  may  be  made  of  some  of  them. 

22.  Project.- -Two  boys  may  secure  a  draw-scale  and  go  out  and 
pull  up  various  weeds  with  it  attached  to  their  stems  and  note  what 
force  is  necessary  to  remove  them  from  their  anchorages.  A  large 
scale  will  be  necessary  if  you  remove  big  weeds.  Bring  the  weeds 
and  the  record  before  the  class. 

23.  Laboratory  Work. — Each  student  may  be  provided  with 
sections  of  the  carrot,  beet,  and  other  roots.     Find  the  epidermis, 


ROOTS    AND    SOILS  I  5 

cortex,  and  stele.     Note  how  the  branch  roots «  ome  off  from  the  stele. 

Scrape  some  of  the  tissue  of  the  carrot  stem  and  examine  under  a 
compound  microscope  to  find  the  various  kinds  of  cells,  especially 
the  spirals  of  the  sap  ducts,  of  which  the  root  is  composed. 

Draw  a  cross  section  of  the  root  and  label  all  of  the  parts. 

24.  Plate  Gardens. — Some  of  the  students  may  prepare  some  glasi 
plates  and  pieces  of  blotter  of  the  same  size  as  the  plates  and  plant 
small  seeds  on  the  surface  of  the  blotter.  Then  place  a  glass  plate 
on  either  side  of  the  blotter  and  tie  a  string  around  them.  Dip 
the  plates  and  blotter  in  water  and  keep  in  a  covered  dish  to  prevent 


-  cortex 


"H-  cambium 


pah 

and 

wood 


Fig.  q. — Diagramatic  cross  section  of  turnip,      (Botany  oj  (  rup  Plant     R 


evaporation.     As  the  seeds  grow  the  root   hairs  are  seen.     Plant 
different  kinds  of  seeds  in  each  garden. 

Note. — Radish  seeds  arc  very  easily  germinated  and  develop  r.»<>t  hair-  which 
are  of  the  best  quality  for  observation.     It'  -prays  of  tin-  wanderii 
cantia)  are   placed    in  water,  they  will  develop  excellent   r.n.t   hair-  and  tip- 

25.  Acid  secretion  of  roots  may  be  shown  by  !rtt:< 
spread  their  roots  in  soil  over  the  surface  of  polished  marble  -lab- 
or blocks.     After  some  weeks  they  should  be  taken  up  and  the  si 
cleaned,  when  a  delicate  etching  may  be  seen  on  1  he  polished  surl 
Another  method  is  to  prepare  a  fluid  (thin)  solution  of  gelatin  and 
litmus.     Add  enough  soda  to  make  it  slightly  alkaline.      Place  it  in 
a  test  tube  and  insert  the  roots  of  a  seedling.     Where  the  n 


i6 


PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 


secrete  acid  the  litmus  will  turn  red.  Care  must  be  taken  to 
avoid  the  growth  of  bacteria  before  the  demonstration  is  complete. 
26.  Individual  Project. — Some  of  the  students  may  plant  the 
seeds  of  squash  or  pumpkin  in  sand.  When  the  seedlings  are  the 
size  shown  in  Fig.  45,  Atwood's  Biology,  they  may  be  pulled  up  if 
the  sand  has  been  allowed  to  become  nearly  dry,  and  the  root  hairs 

will  hold  the  particles  of  sand  as  shown  in 
the  figure.  Show  your  results  to  the  class. 
This  may  be  tried  with  other  kinds  of  seeds. 
What  is  the  value  of  root  hairs  to  the  plant? 
27.  Osmosis  Experiments. — Prepare  an 
egg  osmometer  by  making  an  opening  in 
the  top  of  an  egg  large  enough  to  insert  a 
glass  tube  of  small  diameter.  Insert  the  tube 
and  seal  with  paraffin  or  sealing  wax.  Now 
carefully  chip  away  the  shell  from  an  area  as 
large  as  a  dime  on  the  other  end,  but  do 
not  puncture  the  shell  membrane.  Emerse 
the  egg  in  water  in  a  beaker.  It  is  best  not 
to  let  the  opening  in  the  lower  side  touch 

show  osmosis   through   a      .       .  .     ,         , 

membrane.      Sugar  solu-     the  bottom  of  the  glass. 

tion  is  placed  within  the       The   above  experiment  may  be  modified 

thistle  tube  and  water  is  ,  ^  5JJ  .        .  n 

placed  in  the  large  vessel.    as  shown  in  Gager  s  Fundamentals  of  Botany, 

{Experimental      General   Fig.  44.     A  further  modification  is  to  place 
Science,  Clute.)  .  .  .  ,         .  .       .      .         .   . 

the  entire  egg  in  a  weak  acid  solution  (about 

4    or  5  per  cent)  as  the  shell  is  dissolved  off  the  egg  membrane 

becomes  distended  until  the  egg  is  nearly  spherical. 

28.  The  carrot  osmometer  is  made  by  boring  a  hole  in  the  top  of 
a  carrot  (or  beet)  with  an  auger  and  fitting  a  rubber  stopper  in  the 
opening.  If  the  opening  is  filled  with  a  strong  sugar  solution  and 
the  carrot  is  emersed  in  water  good  results  should  follow.  Make 
more  than  one.     See  Atwood's  Biology,  Fig.  46. 

29.  Cell  turgor  may  be  demonstrated  by  placing  slices  of  beet  in 
strong  salt  water.  Why  do  they  become  flabby.  Place  wilted 
slices  in  water.     Why  do  they  become  turgid? 

30.  Individual  Projects — Choose  two  plants  which  are  easily 
wilted.     Allow  the  soil  in  their  pots  to  become  dry.     When  they 


ROOTS    AND  SOILS  i  ; 

are  willed,  water  one  pot  abundantly  and  cut  the  other  plant  • 
near  its  root  and  put  it  in  a  vase  of  water.  Whit  h  revives  the  tn< 
rapidly?    Of  how  much  value  are  the  roots  and  their  root  hail 

31.  Soils. — The  supplies   committee   should    secure   samples 
sand,  clay,  humus,  and  such  other  kinds  of  soils  as  are  available  and 
prepare  an  exhibit  for  the  class.     Another  cxhil.it    may  be  made 
to  show  the  kinds  of  rocks  which  produce  -and,  clay,  and  lime 
soils  when  they  weather. 

32.  Demonstration.— Hygroscopic  water  may  be  shown  bypla<  ing 
some  soil  in  the  bottom  of  a  test  tube  and  holding  it  in  a  horizontal 
position  over  a  flame  so  that  the  soil  is  heated.  Moisture  will 
collect  on  the  cool  sides  of  the  top  of  the  tube.  Compare  the  amount 
of  such  water  in  sand  and  humus.  Is  it  possible  that  some 
of  the  water  which  comes  from  the  humus  is  due  to  chemical 
decomposition? 

33.  Experiment. — The  value  of  a  mulch  in  conserving  soil  moisture 
may  be  shown  by  working  out  the  experiment  shown  in  Fig.   | 
Atwood's  Biology. 

34.  Capillarity  may  be  demonstrated  for  soils  by  placing  various 
kinds  in  large  glass  tubes  (gas  lamp  chimneys)  which  have  been  - 
up  in  pans.     The  soil  will  lie  against  the  bottom  of  the  pan.     Pour 
water  into  the  pans  and  watch  it  rise  in  the  soil  in  the  tube        \\  hich 
kinds  of  soil  allow  water  to  pass  up  the  most  rapidly? 

35.  Percolation  may  be  demonstrated  with  the  same  apparatus 

is  used  above,  but  the  water  is  poured  into  the  top  of  the  tube  in 
each  case.  Does  it  pass  down  equally  fast  in  all  soils.  What  soils 
will  receive  the  most  rain  water? 

36.  Project. — The  humus  content  of  soils  may  be  demonstrated 
by  weighing  out  a  small  amount  of  dried  soil  on  a  delicate  balan 
and  heating  it  to  redness  until  all  of  the  carbon  of  the  humus  is  burn* 
out.     On  weighing  again  the  difference  in  weight  will  indicate  wl 
proportion    was    composed    of    plant    and    animal    remains, 
experiment  may  be  performed  by  various  -indent-  a-  ap         '  and 
the  results  presented  to  the  1  la--. 

37.  Project.— The   comparative   ability   of   soils   to   hold  wat 
may    be    demonstrated    by    the    experiment    shown    in    Fij  in 
Atwood's  Biology.     Place  a  different  kind  ^\  -oil  in  each  dish  and 

2 


l8  PROJECTS    AXD    EXPERIMENTS    IN   BIOLOGY 

omit   tin-  sawdust.     Do  all  soils  dry  out  with  the  same  rapidity? 
Show  the  results  to  the  class. 

38.  Topic-  The  fixation  of  nitrogen  in  soils  by  the  agency  of 
bacteria.     See  Fig.  21. 

39.  Crop  Rotation. — Consult  references  and  learn  what  this 
means.  What  has  clover  and  other  legumes  to  do  with  it?  What 
would  be  a  good  rotation  for  a  potato  farm?  For  a  farmer  who 
specializes  in  wheat?  In  corn?  In  cotton?  Make  a  diagram  of 
each  of  the  above  mentioned  rotations  on  the  board.  Discuss  them 
in  class  and  let  each  student  make  a  copy  for  his  notebook  when  they 
have  been  corrected.  This  may  be  worked  out  as  a  class  pro- 
ject. The  date  of  the  study  in  class  should  be  set  two  days  ahead 
and  each  student  should  be  given  references  in  the  agriculture  texts 
in  the  library. 

40.  The  value  of  drainage  may  be  shown  by  placing  plants  in 
each  of  two  tin  cans.  Make  holes  in  one  and  leave  the  other  as  it  is. 
Water  them  both  frequently  but  keep  the  can  without  holes  in  the 
bottom  flooded.  After  some  days  note  the  difference  in  the  two 
plants.  How  long  does  the  one  without  drainage  live?  Are  all 
plants  affected  the  same?     How  does  excess  water  damage  roots? 


9.  PLANT  STEMS  AND  FORESTRY 

References 

Experimental  Botany,  Payne,  American  Book  Co. 

Civic  and  Economic  Biology,  At  wood,  Studies  9,  10,  and  11. 

41.  Field  Trip. — Go  to  a  woods  or  a  park  and  study  trees.  Learn 
to  recognize  them  by  the  shape  of  their  stems  and  branches.  Com- 
pare the  thickness  and  roughness  of  the  bark.  Note  also  its  color. 
Compare  the  twigs  as  to  size.  Collect  samples  of  twigs  to  show 
various  kinds  and  arrangement  of  buds,  and  bring  them  to  the 
laboratory.  Place  some  of  the  buds  which  have  been  collected 
after  the  leaves  have  fallen,  in  water  in  the  warm  sunlight.  They 
will  open  and  may  be  studied  as  to  their  scales,  scars,  leaves 
and  flowers. 


PLANT  STEMS  AND  FORESTRY 


[9 


42.  Draw  specimens  of  bucls  and  label  them.     Se<  Fig  6,and 

57  in  Atwood's  Biology. 

43.  Demonstration.- -The  supplies  committee  should  sei  ure  sp< 
mens  of  erect,  climbing,  prostrate,  and  underground  stems  and 
present  them  to  the  class  with  appropriate  remarks  as  to  where  if 
are  found,  how  they  are  related  to  the  environment  of  the  plant,  and 

what  special  advantages  each  provides. 


coro 


—leaf  bud 


growth 


scar 


scales 


/  rjrowfn 


Fig.  ii. — Spur  of  sour  cherry  to  show  (lower  buds.     Compare  with  P 
and  57  in  Atwood's  Biology.      (Botany  0)  ( 'rop  Plants,  Robbin 

44.  Notebook   Work.     Prepare  a  table   listing  the  advanta 
and  disadvantages  of  each  special  kind  oi  stem. 

45.  Project. — Plant    specimens    of   bulbs,    corms,    tubers,    and 
rhizomes.     Give  them  into  the  charge  of  a  committee  and  obs 
them  from  time  to  time  throughout  the  coming  months. 

46.  Draw  cross  sections  of  young  stems  and   label   the  r< 

and  rings  of  tissues  which  appear.     Permanent  slides  may  be  had 
from  dealers.     These  may  be  used  with  the  microscope  or  lantern. 


20 


PROJECTS    AND    EXPERIMENTS   IN  BIOLOGY 


47.  Experiment. — Investigate  the  circulation  of  sap  in  stems  by 
placing  various  kinds  in  red  ink.     They  should  be  in  good  health 


Fig.  12. — Section  of  tulip  bulb  to  show  the  structure  of  a  typical  bulb.     B,  Flower 
bud;  F,  stem;  S,  bud-scales.      (Fundamentals  of  Botany,  Gagcr.) 


Fig.  13. — Photomicrograph  of  a  cross  section  of  a  young  stem  of  Aristolochia 
sipho  to  show  beginning  of  the  formation  of  the  cambium  ring,  a,  Epidermis; 
b,  collenchyma;  c,  parenchyma  of  cortex  and  starch  sheath;  d,  sclerenchyma; 
c  thin-walled  parenchyma  of  the  pericycle;  /,  medullary  ray;  g,  phloem;  h, 
xylcm;  i,  cambium;  j,  pith.      (Plant  Anatomy,  Stevens.) 

and  growing.     The  ink  will  pass  up  in  their  sap  ducts  making  them 
more  easily  seen.     In  what  part  of  stems  does  the  sap  flow  up? 


PLANT  STEMS  AND  FORESTRY 


2  I 


Draw  cross  sections  of  stems  to  show  the  region  where  the  sap 

flows  upward. 

48.  Project.— Plant  portions  of  stems  of  the  willow,  English 
ivy,  and  other  plants  with  their  top  ends  in  the  soil  and  the  bottom 
ends  up.  If  they  are  well  cared  for  they  will  grow  this  way.  \\  bat 
influence  do  you  think  gravity  has  on  the  direction  of  flow  of  sap? 


Fig.    14. — Photomicrograph    of  a   cross    section    <•!"   a   four-year-old 
Aristolachia  sipho.     Note  the  annual  rings  ami  the  compressed  medulla 
The  labeling  is  as  in  the  previous  figure  with  tin-  following  additi 
cambium;  k,  cork;  m,  new  medullary  ray  forming;  n ,  from  thi 
xylem  has  been  formed  from  the  cambium.      {Plant  .1  mitom;.     - 

49.  Reports  and  Topics.-  Will  the  library  committee  prepare 
a  list  of  topics  on  trees  and  forestry  which  are  suitable  for  written 
themes  or  reports?  The  archives  committee  will  consult  with  the 
instructor  when  the  topics  selected  arc  written  up  and  el 

which  should  he  given  to  the  (lass. 

50.  Demonstration.      Show    specimens    of    plane    and   quart) 
sawed  oak   and  other  woods  to  the  class  ami  explain  the  grain 


22 


I'ROJKCTS    AND    KXPERIMENTS   IN  BIOLOGY 


..I  wood.     It  is  due  both  to  the  annual  rings  and  the  medullary 
rays. 

51.  Project. — Find  some  stumps  of  trees  which  have  been  cut 
recently,  measure  their  diameters,  and  count  their  rings.  How  fast 
do  trees  grow?  Compare  the  speed  of  growth  of  hard  and  soft 
woods.     Report  your  findings  in  class. 


Fig.  15. — Transverse  section  through  a  four-year-old  stem  of  white  pine. 
a,  fork;  b,  cortex;  c,  phloem;  d,  cambium;  e,  xylem;/,  secretion  reservoir;  g,  pith; 
h,  medullary  ray.      (Pharmaceutical  Botany,  Youngken.) 

52.  Demonstration. — The  museum  committee  should  prepare  an 
exhibit  of  specimens  of  wood  which  are  ring  porous,  diffuse  porous, 
and  of  evergreens  which  have  resin  ducts  instead  of  pores.  If  no 
specimens  are  in  the  laboratory,  try  to  secure  some.  They  will  show 
their  special  features  better  if  they  are  planed  and  polished  in  the 
department  of  manual  training. 


II    WES 

53.  Committee  Investigation.  Learn  what  trees  are  favored  foi 
street  planting  in  your  city.  Why  are  they  favored?  Make  a  list 
of  our  native  trees  which  are  good  for  city  planting  and  .1  list  which 
are  not.     Give  reasons.     Present  the  results  of  your  inv<  tion 

to  the  class.     For  the  above  information  you  should  visit   the  city 

forester  or  the  citv  clerk. 


Fig.  16. — Photomicrograph  of  a  cp  tion  of  a  corn  stalk  t<->  show  '.he  \ 

of  an  endogenous  stem,     a,  Epidermis;  f>,  cortex  an«l  pericycle;  c,  fundamei 
(pith)  tissue  with  vascular  bundles  interspersed  in  it.     The  large  tul 
bundles   are   xylem,   the   small   tubes   arc   phloem.      {Plant   Ana  torn 


10.  THE  STRUCTURE  AND  WORK  OF  LEAVES 

References 

Civic  mid  Economic  Biology,  Aiwood,  Studies  1 2  and  1 
Experimental  Botany,  Payne,  American  Book  Co. 
Plant  Anatomy,  Stevens,  I'.  Blakiston's  Son  &  Co. 

54.  Types  of  leaves  may  be  studied  by  having  each  student  bring 
as  many  kinds  as  he  ran  find  to  clas       When  colle<  ted,  they  may  be 

sorted     into    three    groups     those    of    the    conifers,    palmate,     md 
pinnate  leaves. 

Note  the  shape  of   the  needles  of  the  pine-  and   spruo         I 
needles  are  flattened,  spruce  needle-  are  square  in  section,  and  pit 


WPEBTT 

.  ( 

24 


• 


PROJECTS    AND    EXPERIMENTS    IN   BIOLOGY 


needles  arc  long.  The  foliage  of  the  hemlock,  arborvitae,  juniper,  and 
cypress  should  be  studied  so  that  it  may  be  recognized  at  sight  if 
these  trees  grow  in  your  locality. 

The  pinnate  leaves  may  come  from  trees,  shrubs,  and  herbs.  Sort 
them  into  their  various  types.  Do  the  same  with  the  palmate  leaves. 

55.  Draw  some  of  the  leaves  which  have  been  brought  in  and 
label  them  with  the  assistance  of  the  figures  in  Study  12  of  Atwood's 
Biology. 

56.  Stomates  may  be  studied  by  carefully  peeling  the  epidermis 
from  the  lower  surface  of  various  leaves  and  mounting  in  a  drop  of 

water  under  the  compound  microscope.  An  onion 
stem,  the  leaves  of  tulips  and  lilies,  and  the  live- 
for-ever  have  an  epidermis  which  is  easily  removed. 
Some  leaves  may  be  viewed  as  opaque  objects, 
and  if  the  light  is  just  right,  the  stomates  may  be 
seen.  Are  there  as  many  on  the  upper  as  on  the 
lower  sides  of  the  leaves?  Can  you  think  of  a 
reason  for  this  variation?  Compare  leaves  which 
stand  erect  with  those  which  are  held  in  a  hori- 
zontal position  on  their  stems. 

Draw    some   stomates  as  you  see  them   under 
the  microscope.     See  Atwood's  Biology,  Fig.  78. 

57.  Topics. — How  do  stomates  open  and  close? 
Why  do  they  do  this?     What  gases  and  vapors 

f  the  Hve-for-ever    pass  in  and  out  through  stomates?    Of  what  value 

to  the  plant  is  this  interchange? 

58.  Notebook  Work  on  Photosynthesis.— Con- 
sult the  following  biologies  and  write  a  description 
of  photosynthesis:  Atwood,  Fig.  80;  Hunter,  p. 
106;  Moon,  Fig.  26.  Answer  the  following  ques- 
tions. What  organs  of  the  plants  perform  this 
work?     What  energy  is  used?     What  materials? 

What  are  the  waste  products?  What  are  the  products  of  this  action 
and  what  is  done  with  them?  Why  is  starch  called  a  carbohydrate? 
Design  a  diagram  to  illustrate  your  topic. 

59.  Transpiration. — Split  a  cork  lengthwise  in  two  parts,  and 
hollow  out  a  groove  in  each  half  to  fit  the  stem  of  a  plant.     Pull  the 


with  a  portion  of 
the  epidermis 
peeled  to  show  the 
method  of  remov- 
ing the  epidermis 
to  view  the  sto- 
mates under  the 
microscope.  {Fun- 
damentals of  Bot- 
any, Gager.) 


LEAVES 


plant  out  of  the  soil  with  its  roots  in  good  condition.     Wash  them. 
Fit  the  halves  of  the  cork  around  the  plant  stem  near  the  n  nd 

put  the  roots  in  a  test  tube  of  water  which  will  hold  them.     I  il  tin- 
cork  in  the  mouth  of  the  tube.     Now  insert  a  fine  glass  tube  in  the 
side  of  the  cork  so  that  air  may  pass  into  the  test  tube,  and  thi 
seal  the  cork  and  plant  in  with  chewing  gum,  paraffin,  or  vaselii 
Weigh   the  plant  and   tube  carefully   and   phut-   in   the   sunlight. 


Fig.    18. — A,   Upper  epidermis  without   stomates;    B,   I  rmi» 

stomates  of  the  fern  Drynoria  meyeniana.     {Heredity  and  Evolution  i 

Gager.) 

Weigh  again  from  day  to  day.     The  only  way  in  which  the  I 
tube  can  lose  water  is  through  the  plant,  as  that  which  comes  out 
through  the  glass  tube  is  negligible.     Make  more  than  one  of  th< 
experiments  and  compare. 

60.  Projects.-  Consult  references  and  set  up  some  of  the  many 
experiments  which  have  been  designed  to  illustrate  transpiration. 
Which  demonstration  is  the  best? 

61.  Diffusion  of  gases  may  be  illustrated  by  the  instructor 
shown  in  the  figure. 


26 


PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 


62.  Guttation  drops  may  be  obtained  by  using  the  split  cork 
and  test  tube  described  in  the  experiment  above.  Place  a  large 
leaf  in  the  tube,  rolled  up  if  necessary,  and  seal  it  in.  The  leaf 
should  be  of  a  plant  which  gives  off  much  water.  The  geranium 
is  not  good  for  this  demonstration.  See  Fig.  81  in  Atwood's  Biology. 
Try  some  other  methods  also.  When  does  water  come  out  of  the 
water  pores  in  leaves?  Do  all  plants  have  them?  Are  guttation 
drops  the  same  as  dew? 

63.  Project. — Arrange  for  a  committee  to  plant  some  seeds  in  the 
dark.     Care  for  them  well,  and  they  will  grow.     Do  they  develop 

any    chlorophyll?     How    long 


NH4CI 


Fk;.  19. — An  experiment  to  show  dif- 
fusion of  gases.  How  does  air  enter  and 
leave  a  leaf?     (General  Science,  Brownell.) 


do  they  live  without  light? 
Report  from  time  to  time  to 
the  class. 

64.  Experiment.  —  Place 
some  green  leaves  in  boiling 
water  for  a  minute  or  two. 
Then  place  them  in  alcohol. 
After  a  time  they  will  be  seen 
to  have  lost  their  chlorophyll. 
Remove  them  and  note  the 
color  of  the  alcohol.     Chloro- 


phyll is  a  green  pigment  composed  of  a  protein  containing  iron  in  the 
"ferrous"  condition.  If  the  alcohol  is  allowed  to  evaporate  the 
chlorophyll  will  remain.     Is  it  still  green? 

65.  Projects. — Make  skeleton  leaves.  See  Payne's  Botany,  p. 
146. 

Make  blue  prints  of  leaves.—- See  Payne's  Botany,  p.  146. 

66.  Demonstration. — Set  up  the  apparatus  shown  in  the  illustra- 
tion and  collect  oxygen  in  the  test  tube  which  is  placed  over  the 
funnel.  Common  ditch  moss  (Elodea)  or  some  other  plant  which 
lives  in  water  will  do.  This  experiment  does  not  work  as  easily  as 
some  manuals  would  lead  the  experimenter  to  believe.  It  must  be 
in  bright  sunlight,  and  when  the  carbon  dioxide  in  the  water  is  all 
gone  it  must  be  given  time  to  collect  from  the  air,  or  it  may  be  made 
from  limestone  and  acid  and  bubbled  in.  How  is  this  experiment 
related  to  photosynthesis?     See  Payne's  Botany,  p.  162. 


I.I.  Wl   - 


67.  Microscope  Work.  Chloroplasts  may  be  seen  in  green  cells 
with  the  compound  microscope.     Secure  some  spirogyra    Se<    I 

184  in  Atwood's  Biology)  or  sonic  ditch  moss    I  and  pla< 

under  the  microscope  in  a  little  water.  I  )<>  riot  gel  any  water  on  the 
stand  of  the  microscope  or  on  the  lense-.  Note  that  the  <  hlorophyl] 
is  confined  to  definite  bodies  within 
the  plant  cell.  They  are  bands  in 
spirogyra,  and  rounded  bodies  in 
Elodea.  If  these  plants  are  not  avail- 
able, various  other  green  plants  will 
do.  Draw  what  you  see  and  label  as 
completely  as  you  can. 

68.  Teacher's     Demonstrations. 
To  Show  that  Plants  Need  Oxygen. 
Follow    directions    as   given    at    the 
bottom  of  p.  96  in  Atwood's  Biology. 

To  Show  that  Plants  Need  Carbon 
Dioxide. — Repeat  as  above  but  put 
in  a  dish  of  pure  sodium  hydroxide 
or  lime  water.  The  dishes  used  in 
these  demonstrations  should  be  wide 
across  and  shallow.  Some  plants  will 
live  a  long  time  under  the  above 
conditions. 

69.  Demonstration.-  Sap  circulates 
through   the   veins  of   plant  leaves. 
Prove  this  by  placing  various  leaves 
and  seedlings  with   leaves  in   red  ink     photosynth.  PaUa 
so  that  it  will  be  absorbed  by  the  lea! 

stem  or  the  roots  of  seedlings  and  sent  out  into  tin-  leavi        N 
that  the  veins  become  red.     A  concentrated  soluti<  ink  will  be 

too  strong.    It  should  be  diluted.     It  may  take  one  or  tw< 
complete  this  demonstration. 

70.  Experiment  to  Demonstrate  the  Presence  of  Starch  in  a 
Green  Leaf.-  Pluck  a  leaf  from  a  geranium  <>t'  the  kind  which 
has  white  markings  on  it s  leaves,  and  which  ha-  stood  in  bright 
sunlight  for  about   two  hour-.     Place  it   in  boiling  water  at   om 


I- 1. 


•  M' 


28  PROJECTS    AND   EXPERIMENTS    IN  BIOLOGY 

Tnal  il  with  alcohol  as  directed  above  in  studying  chlorophyll. 
This  is  to  get  the  color  out.  When  the  leaf  is  no  longer  green,  place 
it  in  a  solution  of  iodine  for  an  hour  or  more,  if  necessary.  The 
blue  color  denotes  starch  and  its  absence  in  the  places  which  had 
no  chlorophyll  indicates  that  it  is  produced  in  the  green  tissue  only. 


ii.  FOOD  AND  ITS  USES 


References 


Civic  and  Economic  Biology,  Atwood,  Studies  14,  15,  and  16. 
.1  Civic  Biology,  Hunter,  Chaps.  XIX  and  XX. 

We  have  seen  how  plants  secure  their  food  by  photosynthesis, 
and  we  will  consider  in  the  work  which  follows  some  of  the  food 
problems  of  animals.  We  should  keep  in  mind  the  fact  that  plants 
make  their  food  from  water,  carbon  dioxide,  and  mineral  salts;  and 
that  animals  use  the  food  which  plants  have  elaborated  not  being 
able  to  make  it  themselves. 

71.  Problem.— How  do  molds  get  their  food?  Place  some  moist 
bread  in  a  covered  dish  so  that  it  will  not  dry  out  and  keep  it  in 
the  dark.  Does  mold  need  sunlight?  Has  it  chlorophyll?  Does  it 
use  the  same  foods  as  green  plants? 

72.  Dissolve  some  glucose  or  corn  sirup  in  water  and  add  some 
yeast.  Put  it  away  in  a  warm  place  in  the  dark.  Does  the  yeast 
grow?     Compare  it  with  a  mold  in  its  food-getting. 

73.  Notebook  Work. — Write  an  article  on  the  food-getting  of 
green  plants  as  compared  with  yeasts,  molds,  and  bacteria.  The 
archives  committee  will  select  a  few  of  the  best  to  be  read  to  the 
class. 

74.  Euglena. — It  may  be  possible  to  get  some  euglena  from  a 
pond.  If  not,  they  may  be  had  from  Powers  &  Powers,  Station  A, 
Lincoln,  Nebraska,  or  from  some  other  dealer.  Observe  them  under 
the  microscope.  How  do  they  move?  Can  they  swim?  If  so, 
how?  Note  that  they  are  green.  This  is  due  to  chlorophyll.  They 
live  like  a  plant,  and  have  the  advantage  of  being  able  to  go  from 
place  to  place. 


FOOD    AND    ITS    l> 

Draw  several  euglena  in  different  positions.     Can  you  show  the 

nucleus,  eye  spot,  and  gullet?     It  will  probabl)  nol  be  possible  to 
see  the  lash. 

The  author  has  kept  a  culture  of  a  green  protozoan, 
the  euglena,  in  an  aquarium  in  the  Laboratory  for 
Try  to  make  a  culture  of  euglena.     Place   it    in    the   chargi 
a  committee. 

75.  Notebook  Work. — Animals  are  divided   into  herbivorous  or 
carnivorous  groups  according  to  whether  they  eat  vegetable  or  animal 
food    respectively.     Some,   as    man    eat    both.     They   are   called 
omnivorous.     Make   a   table   of   the  vertebrate  animal-  assign! 
them    to    one  or  the  other  of  the   three  clas  Bears  and  d« 
are  carnivores  in  spite  of  the  fact  that  they  eat  large  quantitii 
vegetable  food.     Discuss  all  doubtful  cases  before  placing  them  in 
the  table. 

76.  Project. — Make  several  balanced  aquaria  and  place  each  in 
charge  of  a  student.     Observe  them  from  time  to  time  a-  the-  phi: 
and   animals  grow.     Do   they   all   stay   balanced?     See    At  wood's 
Biology,  Figs.  86,  87,  and  356.     See  also  Hunter,  p.  [66;  Hodge  and 
Dawson,  p.  13,  299,  315. 

77.  Notebook  Work. — Consult  some  of  the  following  referent 
and  make  diagrams  of  the  chemical  cycles  listed  below:  Atwood, 
Figs.  9,  82,  and  86;  Gruenberg,  Chap.  XIV j  Moon,  Chap.  1.III; 
and  Hunter,  Chap.  XIV.  Diagram  the  carbon  cycle  first,  then  the 
nitrogen  cycle,  and  then  the  food  cycle.  Use  a  ruler  and  i.»m- 
pass  in  drawing  your  lines  so  they  will  be  uniform  and  neat. 
If  time  permits,  it  will  be  well  to  write  note-  explaining  each 
diagram. 

78.  Food  Plants. — See  p.   102,  Atwood 's   Biology,  and  make 
table  of  the  common  plants  which  are  used  a-  food.      In  cadi 
we  use  the  roots,  stems,  leaves,  flowers,  fruits,  or  seeds.      \ 
each  plant  to  its  proper  place  in  the  table.      It  may  be  well  'k 
this  table  out  on  the  board  as  a  class  proje<  1,  after  which  it  ma\ 
copied  in  the  notebooks. 

79.  Caloric  values  of  foods  have  been  overstressed  of  late 
If  it  is  desired  to  do  such  work,  a  reference  may  be  consulted. 
At  wood's  Biology,  p.  107. 


3° 


PROJECTS    AXD    EXPERIMENTS    IN   BIOLOGY 


A//T/?OGf/V  Or  A//r> 

t 


I 


I 


I 


i/vftTiT  r/y^r/OAf 


U 


i 


(YOOIU.£, 


S^ETO  TO  ANtMALS 


G/?£EN- 


-rA&W 


P  /    1 


L  . 


/*7Aqt/fr£- 

Ml/Ait/S 

4/ 


Fig.  21. — The  nitrogen  cycle  as  shown  in  the  life  of  an  alfalfa  plant.      {General 

Science,  Brownell.) 


Fool)    AND    ITS    I'M 


80.  Topic— Insectivorous  plants  capture  insects  and  digest  them. 
Pitcher-plants,  sundew,  and  the  Venus  fly-trap  are  described  and 
illustrated  in  Interesting  Neighbors,  Jenkins.  P,  Blakiston's  Son  8  I 


Fig.   22. — The  Venus  fly-trap,   the  leaves  of  whirl)   captu 

{Heredity  and  Evolution  in  Plant     C     tr.) 


Compare  the  food-getting  ol  these  plants  with  other  plants  and 
animals.     In  what  situations  do  they  livi        I    their  habitat  lacking 

in  essential  plant  foods? 


32 


PKOJECTS   AND   EXPERIMENTS   IN  BIOLOGY 


12.  CHEMICAL  FOOD  TESTS 


Reference 
Civic  and  Economic  Biology,  At  wood,  Studies  14,  15,  and  16. 

The  following  tests  may  be  made  by  each  member  of  the  class  if 
laboratory  facilities  permit;  or  they  may  be  performed  as  a  demon- 
stratioD  from  the  lecture  table.  Each  should  be  written  up  carefully 
in  the  notebook.  See  Atwood,  Study  15;  Hunter,  the  last  half  of 
Chap.  II;  and  Payne's  Botany,  pp.  19-29. 

81.  Carbon  Test. — Place  bits  of  cloth,  wood,  feathers,  etc., in  small 
test  tubes  containing  small  amounts  of  concentrated  sulphuric  acid. 
The  acid  decomposes  organic  compounds  and  extracts  water  leaving 
the  carbon  to  color  the  contents  of  the  tube  black.  It  may  be 
necessary  to  let  some  tubes  stand  for  quite  a  while. 

82.  Starch  Tests. — Starch  is  not  soluble  as  it  exists  in  plants, 
therefore  it  will  be  necessary  to  boil  some  starch  in  a  test  tube  of 


PlG.  23. — Starch  cells  of  a  potato  before  and  after  being  cooked.     Describe  what 
has  happened.      {General  Science,  Brownell.) 

water.  Cool  it.  Add  a  few  drops  of  a  solution  of  iodine.  The 
starch  is  changed  to  starch  iodide  which  is  blue.  Heat  it,  the  solu- 
tion should  be  clear.  If  it  is  cooled  again,  the  blue  color  returns. 
Iodine  may  be  dissolved  in  water  if  a  few  crystals  of  potassium  iodide 
are  dissolved  first.  This  is  better  than  an  alcoholic  solution.  Test 
various  foods  for  starch.  Is  there  any  starch  in  sugar?  In  corn 
sirup?     In  honey?     In  mucilage? 

Scrape  a  raw  potato  and  place  some  of  the  pulp  under  a  compound 
microscope.     The  starch  grains  have  an  appearance  somewhat  like 


Rye. 


Buckwheat 

r 


. 


T 


>> 


_s-_L-_ 


Bean. 


Ah  k<  »\\  : 


Barley. 


Oat. 


TJg 


Maize. 


Rut:. 


- '  &i 


I 


^> 


'■ 


Pica. 


Win  \  1 . 


Fig.  24. — Various  types  of  starch  grain  een  under  th 

Analysis,  I.c/J'tnann  and  Beam.) 


34  PROJECTS    AND    EXPERIMENTS   IN  BIOLOGY 

an  oyster  shell.  Grains  of  starch  from  different  plants  have  a 
different  appearance.  Examine  several  kinds  in  water.  Can  you 
tell  from  what  plant  a  sample  of  starch  came  by  examining  the 
grains?  Can  you  tell  if  potato  starch  has  been  mixed  with  corn 
starch? 

83.  Glucose  Test. — When  a  solution  containing  glucose  is  heated 
with  Fehling's  solution  the  copper  in  the  test  fluid  is  oxidized  by  the 
glucose,  and  yellow  to  deep  orange  copper  oxide  appears  in  the  test 
tube  as  a  precipitate. 

Fehling's  solution  may  be  made  as  follows:  Dissolve  34.65  grams 
of  copper  sulphate  in  500  cc.  of  water  and  put  in  a  bottle.  In 
another  bottle  containing  500  cc.  of  water  dissolve  125  grams  of 
sodium  hydroxide  and  173  grams  of  Rochelle  salt  (sodium-potassium 
tartrate).  Keep  the  solutions  separate  until  shortly  before  they  are 
to  be  used  when  they  are  mixed  in  equal  parts  to  form  Fehling's 
solution. 

Heat  a  dilute  mixture  of  glucose  and  Fehling's  solution  in  a  test 
tube.  Note  the  beautiful  deep  orange  to  red  color.  Try  this  with 
various  foods,  especially  cane  sugar,  starch,  mucilage,  and  flour. 

Place  some  ground  cracker,  flour,  or  starch  in  water  and  add  some 
diastase  or  saliva.  After  a  few  minutes  test  with  Fehling's  solu- 
tion.    What  is  the  action  of  these  two  ferments  on  starch? 

84.  Protein  Tests. — Prepare  some  white  of  egg  in  water. 

1.  The  heat  test  is  made  by  placing  some  of  the  solution  in  a  test 
tube  and  boiling.  A  cloudy  appearance  indicates  the  presence  of  a 
protein  which  coagulates  when  heated. 

2.  The  xanthoproteic,  or  yellow  test,  is  made  by  placing  nitric  acid 
on  some  egg  white  in  the  test  tube  and  heating  gently.  It  should 
turn  yellow.  Now  pour  out  the  excess  liquid  and  add  enough 
ammonium  hydroxide  to  neutralize  the  acid.  A  deep  orange  color 
should  appear. 

3.  The  burning  test  is  made  by  burning  a  piece  of  meat  or  a 
feather  and  noting  the  odor. 

4.  The  sugar  test  is  made  by  adding  a  drop  of  concentrated  cane 
sugar  solution  to  the  protein  solution  in  a  test  tube  and  then  adding 
a  drop  or  two  of  pure  concentrated  sulphuric  acid,  when  a  deep 
red  color  appears. 


CHEMICAL    FOOD    TKSTS 

(Millon's  test  and  the  biuret  test  give  a  red  and  a  violet  color 
respectively.     They  may  be  found  described  in  Hawk's  Physiolog 
ical  Chemistry,  and  Payne's  Botany.     They  are  both  very  deli< 

tests.) 

Apply  some  of  the  tests  described  above  to  various  kinds  of  foa 

85.  Fat  and  Oil  Test.-  Foods  which  contain  much  oil  will  mal 
grease  spot  on  paper.     It  may  be  necessary  to  grind  the  material 
very  fine  and  press  it  against  the  paper.     A  gentle  heat  may  be  of 
some  aid.     Be  sure  that  the  spot  is  not  a  water  spo  1  by  giving  it  time 
to  dry  or  by  warming  it.     If  it  is  an  oil  spot  it  will  May. 

Soudan  III  may  be  had  from  the  dealers.  It  is  a  dye.  Place  it 
on  the  grease  spot  and  then  wash  the  spot  with  alcohol.  N  tin- 
color. 

86.  Water  or  Moisture  Test— Place  some  of  the  material  to  In- 
tested  in  a  test  tube  and  hold  in  a  horizontal  position  over  a  flame 
so  as  to  heat  the  material  in  the  bottom  of  tin-  tube-  without  heating 
the  top  of  the  tube.  If  moisture  is  present,  it  will  collect  >>n  tin- 
sides  of  the  tube.  If  the  material  is  strongly  heated  the  moisture 
may  result  from  the  chemical  decomposition  of  tin-  substance  which 
is  tested. 

87.  Test  for  Mineral  Matter. — This  is  sometimes  called  tin-  ash 
test.  Heat  the  material  to  be  tested  in  a  crucible  until  it  i-  red. 
Keep  it  so  for  a  long  time.  If  anything  remains  it  is  mineral  matter 
which  will  not  burn  or  pass  off  as  a  vapor. 

Free  salts  in  a  soluble  condition  may  be-  detected  by  soaking  tin- 
material  to  be  tested  for  a  time  in  water  and  then  altering  the  water 
and  allowing  it  to  evaporate,  when  they  will  be-  Kit  a-  crystals. 

88.  Review. — How  can  you  detect   starch   in  pulverized   sug 
Starch  in  glucose?     Salt  in  meat?     Starch  in  ice  cream?     Glu 

in  candy?  Starch  in  candy?  Wool  from  cotton?  Salt  in  butter? 
Limewater  in  milk  to  keep  it  sweet?  Barley  flour  in  wheat  flour? 
Starch  from  flour?     Glue  from  mucilage?     [f  a  disput  d><»ut 

any  of  these  questions  it   should   be  tried  out.     that  i-  th<  1. 

89.  Milk  Tests.     Sour  milk  may  be-  tested  for  by  placing  a  strip 
of  blue  litmus  in  it.      If   tin-   litmus   turn-   red,   tin-   milk    i- 
Another  test  is  to  put  some  soda  in  the  milk.      If  it  efferv*  the 
milk  is  sour.     Explain  tin-  chemical  action.     1-  sour  milk  us< 


PROJECTS    AMI    EXPERIMENTS    IN  BIOLOGY 

cooking?     Explain.     Smell   and    taste   are   also   good   methods   of 
testing  sour  milk. 

90.  Butter-fat  tests  of  milk  are  made  by  centrifuging  the  fat 
from  the  rest  of  the  milk  or  dissolving  out  the  fat  in  ether.  The 
Babcock  milk  test  is  most  frequently  used,  but  the  ether  test  is 
more  accurate.  Get  State  and  Government  bulletins  from  the 
agricultural  departments  which  give  directions  for  making  the  test. 
Also  see  Bowden's  General  Science,  p.  574.  The  test  may  be  made 
before  the  class  as  a  demonstration.  If  we  should  give  complete 
directions  for  making  the  test  here,  it  would  require  too  much  space, 
as  there  are  many  difficulties  to  avoid. 

91.  The  formaldehyde  test  is  made  by  placing  some  milk  in  each 
of  two  beakers.  To  one  add  a  small  amount  of  formaldehyde  and 
leave  the  other  as  it  is.  Place  a  drop  or  two  of  a  solution  of  ferric 
chloride  in  some  pure  hydrochloric  acid.  Add  twice  as  much  of 
this  acid  to  each  of  the  beakers  of  milk  as  there  is  milk.  Mix  the 
milk  and  acid  well  by  rotating  the  beakers.  Place  them  both  in 
boiling  water  for  some  minutes.  The  milk  which  contains  formalde- 
hyde becomes  lavender  to  purple  in  color.  Why  is  formaldehyde 
added  to  milk?  To  determine  this  take  two  samples  of  fresh  milk 
and  add  a  few  drops  of  formaldehyde  to  one  and  none  to  the  other. 
Set  them  away  and  observe  which  becomes  sour  first.  Formaldehyde 
is  a  dangerous  poison,  and  must  not  be  used  in  preserving  milk. 


13.  DIGESTION 

References 

Civic  and  Economic  Biology,  Atwood,  Study  16. 
Elementary  Biology,  Gruenberg,  Chap.  XIX. 

92.  Committee  Project, — Dissect  one  or  more  frogs  to  show  the 
digestive  system.  Spread  the  specimens  under  water  in  pans  and 
show  to  the  class.  The  organs  may  be  drawn  and  labeled.  Ward's, 
Rochester,  N.  Y.  have  a  model  of  a  frog  which  may  be  set  up 
before  the  class  and  its  organs  drawn.  Other  preparations  may  be 
had  of  the  specimens  in  glass  jars  with  the  organs  dissected.     The 


DIG]  STION 


nasal  cavity 


PALATE 


MOUTH  CAVITY    A* 


NASAL  Pit'. 


OHAL  PHAR\  I 
LARWvJEAL  PHARYNX 


BILE  AND 

PANCREATIC 

DUCTS 


RIGHT  COLIC 
FLEXURE 


DUODENUM 


LEFT  fOUC 
V*^9^T.  .     .    v\\      FLEXURE 

XI 


VERMIFORM 
PROCESS 

Fig.  25. — Diagram  of  the  alimentary  canal 

Morri 


,SS  PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 

museum  committee  may  make  some  preparations  of  various  animals 
and  preserve  them  in  glass  jars  in  formalin. 

93.  Notebook  Work. — Make  a  drawing  of  the  digestive  organs  of 
some  animal,  or  of  man;  label  the  parts,  and  name  the  digestive 
juices  which  each  organ  supplies. 

94.  Consult  Fig.  91  in  Atwood's  Biology;  pp.  275  and  343  in 
Hunter's  Biology;  Figs.  28  and  32  in  Gruenberg's  Biology;  Fig.  114 
in  Moon's  Biology;  or  Figs.  178  and  165  in  Smallwood's  Biology  and 
write  a  description  of  the  similarities  and  differences  in  the  digestive 
systems  of  the  frog  and  man. 

95.  If  it  is  desired  to  make  a  study  of  the  teeth,  consult  Eddy's 
Experimental  Physiology  and  Anatomy,  p.  60. 

96.  Salivary  digestion  was  illustrated  in  connection  with  the 
study  of  Fehling's  solution  as  a  test  for  glucose,  which  see  if  it  is 
desired  to  make  a  further  study  of  its  action.  Does  it  act  in  an  acid 
medium?     In  an  alkaline  medium? 

97.  Exercise. — Commit  to  memory  the  table  of  digestive  juices 
given  on  p.  112  of  Atwood's  Biology  and  write  it  as  a  test. 

98.  Notebook  Work. — Write  a  description  of  the  passage  of 
digested  food  from  the  intestine  to  the  blood  system.  How  does  it 
get  through  the  walls  of  the  intestine?  Which  foods  go  through  the 
liver  ?  Which  through  the  lymphatic  system  ?  See  Atwood's  Biology, 
Fig.  93;  Moon,  Fig.  121;  Hunter,  p.  354;  and  Gruenberg,  p.  87. 

99.  Digestion  Experiment. — Pepsin  may  be  had  from  drug  stores 
or  from  dealers  in  biological  supplies.  Prepare  some  boiled  egg. 
Mince  the  white  very  fine.  Place  some  pepsin  solution  in  four  test 
tubes.  To  the  first  add  nothing,  to  the  second  add  a  drop  of  dilute 
hydrochloric  acid,  to  the  third  add  several  drops  of  dilute  hydro- 
chloric acid,  and  to  the  fourth  add  two  drops  of  an  alkali  (NaOH). 
Place  some  minced  egg  in  each  test  tube  and  stand  away  in  a  warm 
place  for  one  or  two  days.  In  which  of  the  tubes  has  digestion  taken 
place?  Why  did  it  not  take  place  in  all  of  the  tubes?  In  which 
did  it  go  on  the  most  rapidly?  This  experiment  may  be  performed 
by  each  of  four  or  five  students  and  the  entire  class  may  view  the 
results  if  time  and  space  are  limited.  Write  it  up  completely  in  the 
notebooks  and  state  which  tube  was  the  most  representative  of  the 
actual  conditions  which  exist  in  the  stomach. 


RESPIRATION    AND   <  lk<  I  LATION 

ioo.  Pancreatin  may  be  used  in  a  similar  manner  to  illu 
intestinal  digestion.     The  only  place  when-  faU  in 

the  intestine.     If  you  wish  to  digest  fats,  use  corn  oil, 
oil,  or  olive  oil.    The  pancreatin  musl  be  fresh  and  of  the  besl  quali 

or  results  will  be  disappointing.     Ii  may  be  made  alkaline  byaddi 
a  little  sodium  carbonate. 

101.  An  emulsion  may  be  made  to  show  to  the  i  lass  by  mixinj 
light  vegetable  oil  with  a  dilute  alkali  and   shaking       D  be 
fat  remain  emulsified?     For  how  long?     Soap  will  form  from   tl 
emulsion  if  it  is  left  to  stand  or  is  warmed.     An  understands 

the   chemistry   of  soap-making   is   helpful   in    understanding    the 
digestion  of  fats. 

102.  Absorption. — Our  problem  here  is,  why  are  foods  digested? 
Use  two  diffusion  shells  such  as  are  sold  by  the  dealers  in  biological 
supplies.  Suspend  each  in  a  vessel  of  water.  PL  >me  starch 
which  has  been  mixed  with  cold  water  in  one  and  some  glucose  <»r 
honey  which  has  been  diluted  slightly  in  the  other.  After  some 
time  test  the  water  in  the  first  vessel  for  starch.  Test  the  water  in 
the  second  vessel  for  glucose.  Did  the  starch  osmos<  Did  the 
glucose?  Which  digestive  juices  change  starch  into  glu<  Why 
is  this  necessary? 

14.  RESPIRATION  AND  CIRCULATION 

Reference 
Civic  and  Economic  Biology,  Atwood,  Study  17. 

103.  Teacher's  Demonstration.     Secure  some  defibrinat         un- 
clotted)  blood  from  a  butcher,  or  by  killing  a  chicken,  and  put  it  ii 
bottle.     Pass  carbon  dioxide   through   tin-   blood   rapidly   from 
generator.     Note  that  the  blood  becomes  a  deep  purple  in  1 
Look  at  the  veins  in  the  wrist   and  compare.     N  >w  pas    oxygen 
through   the  blood.     It   become?   a  bright  scarlet.     I  (plain   h- 
carbon  dioxide  and  oxygen  are  carried  by  the  haemoglobin  in  t; 
blood.     Why  is  the  blood  which  flows  from  a  cul  always  r< 

Pass  carbon  monoxide  gas  through  the  blood  and  n 
becomes  a  carmine  red  m  c<  '   '•     In  dilute  solutions  it 


4° 


PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 


/In 


bluish-red.     Carbon  monoxide  has  such  a  strong  affinity  for  haemo- 
globin that  it  can  not  be  replaced  by  oxygen  as  can  the  dioxide. 
Does  this  explain  why  it  is  a  deadly  poison?     Can  the  presence  of 
carbon  monoxide  be  detected  by  its  odor?     Why  is  it  dangerous  to 
be  in  a  closed  room  with  a  gasoline  engine  running? 

In  the  above  demonstration,  the  carbon  dioxide  may  be  obtained  by  placing 
hydrochloric  acid  on  lumps  of  limestone.  The  oxygen  may  be  obtained  from 
the  air  and  may  be  pumped  through  with  a  bicycle  pump.  The  carbon  monoxide 
may  be  had  by  passing  gas  from  the  gas  jet  through  the  blood,  or  it  may  be  made 
by  placing  concentrated  sulphuric  acid  on  crystals  of  oxalic  acid  in  a  generating 

flask. 

The  technical  words  used  in  this  study  should  be  carefully  spelled  on  the  board, 
and  the  experiment  written  up  in  the  notebook. 

104.  The  function  of  the  diaphragm  in  respiration  may  be  shown  as 
in  the  figure.     A  piece  of  dentist's  rubber  sheeting  may  be  tied  over 

the  bottom  of  the  vessel.  Place  a  button 
in  its  center  and  fasten  a  string  around 
the  button  and  the  rubber.  A  toy 
balloon  may  be  placed  on  the  inside  of 
the  glass  vessel.  Write  an  explanation 
of  this  demonstration. 

105.  Notebook  Work. — From  a  model 
of  the  heart,  from  charts,  from  illustra- 
tions in  texts  (Atwood,  Fig.  99),  or  from 
a  pig's  heart  describe  the  circulation  of 
the  blood  through  the  heart. 

The  circulation  of  the  blood  of  the 
earthworm  may  be  described  from  Fig. 
95,  Atwood'' s  Biology.  A  dissection  to 
show  these  vessels  may  be  made  by  some  student  as  a  project,  but 
it  is  usually  only  a  partial  success  as  a  class  dissection.  Put  the 
dissected  specimen  in  the  museum  case. 

106.  The  operation  of  the  tracheal  system  of  an  insect  may  be 
described  from  Figs.  33  and  96,  Atwood' s  Biology. 

107.  Red  blood  corpuscles  may  be  studied  under  the  microscope 
as  directed  in  Eddy's  Experimental  Physiology  and  Anatomy, 
p.  72. 


Fig.  26. — Apparatus  for  an 
experiment  to  show  the  effect 
on  the  lungs  of  depressing  the 
diaphragm.  (Elements  of 
Animal  Biology,  Holmes.) 


TROPISMS    AND    !■:  I  SPl  ►]  41 

108.  The  circulation  of  the  blood  in  the  frog's  foot 
strated  as  directed  in  Eddy,  ]>.  70. 

109.  The  Air  in  the  Lungs.     Blow  the  breatl 

of  cold  glass  or  metal.     \\  hal  1  olle<  1  -  on  the  surfai  e  of  the  . 
metal?     Blow  gently  on  the  hull)  of  a  thermometer.     Whal  hapr* 
Blow  slowly  through  a  glass  tube  int..  a  glass  of  fresh  lin         tcr. 
What  causes  the  cloudy  appearance  of  the  limewati         Wriu 
statement  in  your  notebook  telling  what  you  have  learned  from  th< 
tests.     When  a  fire  hums  what  are  the  produi  I        <    >mpare  with 
the  statement  which  you  have  just  written. 

no.  Project. — Two  hoys  may  weigh  themselvi  irately 

before  athletic  practice  and   again   after.     What    became   of   the 
materials  which  were  lost?     How  is  the  energy  of  exei  irnisl 

in.  Lung  capacity  may  be  determined  by  filling  a  la 
vessel,  as  a  bottle,  with  water  either  before  or  after  inverting  it  in 
another  and  larger  vessel  of  water.     Insert  a  large  glass  or  rubl 
tube  under  the  vessel.     After  taking  a  normal  breath  the  air  from 
the  lungs  should  be  blown  into  the  inverted  glass  vessel.      \ 
venient  scale  of  measurement  should  be  applied  to  the  side  ol  tl 
vessel.     Now  fill  the  lungs  full  to  capacity  and  repeat.     Compare 
with  others.     Sterilize  the  end  of  the  tube  which  you  put  in  your 
mouth.     In  the  average  student's  lungs  there  will  remain  about  ic 
cubic  inches  of  air  after  all  has  been  expelled  which  can  be  «lri\  < 
out.     What  is  your  average  lung  capacity?     What  is  your  maximum 
capacity? 

15.  TROPISMS  AND  RESPONSES 

References 

Civic  and  Economic  Biology,  Atwood,  Unit  III. 
Experimental  Botany,  Payne,  American  Book  l 
The  Animal  .\fin<!,  Washburn,  Macmillan  I 

112.  Projects.     Geotrcpism  is  the  response  of  a  plant  to  the 
of  gravity.     It  may  be  shown  by  the  following  metha        \\ 
they  are  ready  they  should  be  shown  to  the  class 
who  has  the  projecl  in  charge.  et  up  the  apparatus 

in  Atwood's  Biology,  Fig.   103;  also  read  p.  and  set  up  1 


42 


PROJECTS   AND   EXPERIMENTS   IN   BIOLOGY 


apparatus  of  Fig.  221.  (2)  Perform  the  experiment  shown  in 
Payne's  Botany,  Figs.  39  and  40,  and  also  in  Moon's  Biology, 
Pig.  10. 

113.  Hydrotropism. — Perform  as  projects  the  experiments  shown 
in  the  references  following  and  report  to  the  class  as  they  are  ready. 
Atwood,  Fig.  104;  Moon,  Fig.  11;  Payne,  Exps.  77,  78,  79,  80,  and  81. 
See  also  Hunter,  p.  73,  and  Gruenberg  Chap.  IX. 


Fig.  27. — Apparatus  for  the  demonstration  of  positive  hydrotropism  of  roots. 
Must  this  attraction  be  stronger  than  gravity  in  this  case?  Use  a  wire  basket 
and  fill  it  with  bog  moss  and  sawdust.  Keep  it  moist.  (Palladin's  Plant 
Physiology,  Livingston.) 

114.  Phototropism. — Refer  again  to  the  experiment  where  a  plant 
was  placed  in  the  dark  with  light  admitted  through  an  opening 
(Fig.  1).  Also  to  the  compass  plant  Fig.  108  in  Atwood's  Biology. 
The  rex  begonia  is  an  excellent  plant  to  show  phototropism.  It  is 
shown  in  Fig.  8,  Atwood's  Biology.  See  Moon,  p.  88;  Hunter,  p. 
100,  and  Gruenberg,  Chap.  IX.  Heliotropism  is  another  word  for 
phototropism. 

115.  Thigmotropism  may  be  demonstrated  before  the  class  by 
touching  the  leaves  of  the  sensitive  plant,  and  by  touching  an  earth- 


TRQPISMS    AND    RESP0NS1  - 


worm  or   a  frog  with   a   bristle.     Touch   the  animals  in   various 
places  and  determine  if  they  arc  equally  sensitive  in  all  partsof  their 

bodies. 

116.  Thermotropism,  with  its  minimum  and  optimum  effe 
may  be  shown  by  preparing  a  trough  as  shown  in  the  illustrate 
and  placing  in  it  some  water  inhabiting  animals.  The  temperature 
of  the  warmed  end  should  not  get  above  o8°F.,  and  tin-  temperature 
of  the  end  which  is  cooled  with  ice  will  be  about  ^  I .  The  parti- 
tions should  go  to  the  bottom  and  may  be  held  in  plan-  with  -and. 
They  are  to  prevent  convection  currents  from  warming  the  entire 
trough,— or  cooling  it.     Place  a  thermometer  in  ea<  h  compartment 


MINI  MUM 


OPTI  MUM 


MA  X  I  MUM 


Gtt^lZt 


C-+.  m „ ,_ >^_-.'-i 


vV'7  l  r-1 


:)■ 


T 


HEAT 


Fig.  28. — Diagram  of  a  tank  to  show  how  animals  seek  optimum  conditi 

which  to  live. 


and  record  the  temperatures  on  the  board.  This  demonstration 
should  be  started  about  two  hours  before  it  is  to  be  shown  to  the 
class.  There  will  be  considerable  difference  in  the  results  obtained 
with  different  kinds  of  animal-.  The  more  a<  tive  they  are  th<  ner 
they  will  respond. 

117.  Trial  and  error  reactions   may   be  observed   1>>    watching 
paramecia  under  a  microscope.     Place  some  -»  urn  in  the  water  win 
they  are  and  note  how  they  colled  around  it.      Plao  ry  -mall 
crystal  of  salt  in  the  drop  where  they  are  and  note  how   the)   acl  in 
reference  to  it.     The  entire  class  may  work  at  this  if  there  are  enouj 
microscopes. 

118.  Draw  a   diagram   of  a   nerve  cell   and   label   all  of  tin   pa 
How  does  the  impulse  enter  the  cell?     What  is  its  COUJ  \\ 
does  it  pass  out  of  the  cell? 


44  PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 

119.  Topic— What  is  the  nature  of  the  nervous  impulse?  Is  it 
electrical?  1-  it  chemical?  Does  it  take  time  to  travel,  or  is  it 
instantaneous? 

120.  Draw  various  types  of  antennae  of  crustaceans  and  insects 
from  specimens.  A  hand  lens  may  be  necessary  to  see  the  joints  of 
insects'  antennae.     See  Figs.  115,  116,  117,  118,  and  120,  Atwood's 

Biology. 

121.  Draw  a  diagram  of  the  human  ear  from  some  book  or  model. 
Label  all  of  the  parts  carefully  and  be  able  to  reproduce  it,  when 
asked,  from  memory. 

122.  Demonstration. — Consult  a  physics  text  and  set  up  a  pen- 
dulum to  demonstrate  the  laws  of  amplitude,  of  length,  of  material 
of  the  bob.  This  may  be  written  up  in  the  notebook  after  it  is  given 
to  the  class. 

123.  Consult  the  physics  text  again  and  set  up  a  sonometer  to 
illustrate  the  four  laws  of  strings.  They  are  the  law  of  length,  of 
tension,  of  diameter,  and  of  material  of  which  the  string  is  composed. 
Write  this  up  also  and  state  how  sound  is  produced.  If  these  experi- 
ments have  been  performed  in  the  classes  in  general  science,  a  review 
only  should  be  given  now. 

124.  Student's  Demonstration. — Stand  before  the  class  and  hold  a 
reading  glass  before  a  cardboard  screen  so  that  it  will  form  an  image 
of  the  window,  or  some  object  out  of  doors.  Consult  a  good  physics 
text.  What  is  an  image?  What  ways  are  there  of  forming  them? 
What  is  a  virtual  image?  A  real  image?  Which  kind  is  formed  on 
the  retina  of  the  eye?  If  the  room  can  be  partly  darkened,  an  image 
of  a  burning  candle  may  be  made  to  fall  on  the  screen. 

125.  Draw  a  diagram  of  the  human  eye  in  the  notebook  and  label 
all  of  the  parts.  Be  able  to  reproduce  the  drawing  and  the  names  of 
the  parts,  when  called  on  to  do  so,  from  memory. 

126.  Draw  a  diagram  of  the  brain  of  the  frog  from  Ward's  models 
of  the  brains  of  typical  vertebrates  (Ward's,  Rochester,  N.  Y.). 
Label  the  parts  carefully,  and  learn  the  names  of  the  parts  of  the 
brain,  and  the  cranial  nerves.  See  Fig.  136  and  the  table  on  p. 
160  of  Atwood's  Biology.     See  also  Fig.  43  in  this  book. 

127.  Social  Recitation. — It  is  usually  valuable  to  devote  one 
laboratory  period  to  an  interchange  of  ideas  and  experiences  on 


PROTOZO \\S 

animal  intelligence,  as  it  has  been  observed  by  the  members  of  I 
class.     There  may  be   evidences  of   superstition,   im 
vation,  faulty  memory,  etc.  on  the  part  of  some  studei 

128.  Debate.     Resolved  that  the  dog  can  and  dees  reason.     I 
this  debate  your   most  conflicting   arguments   will   (inter  ai    1 
the  proposition,  "What  is  reason?" 

16.  STUDIES  OF  PROTOZOANS 

References 

General  Zoology ',  Pearse,  Henry  1 1« >I t  and  Co. 

General  Zoology,  Linville  and  Kelly,  Ginn  &  Co. 

Practical  Zoology,  Hegncr,  Macmillan  Co. 

Life  of  Inland  Waters,  Ncedham  and  Lloyd,  Comstock  Pub.  < 

The  Protozoa  of  Iowa,  Edmondson,  Davenport  Acad,  of  &  i. 

Civic  and  Economic  Biology,  Atwood,  Study  25. 

129.  The  Ameba. — These  animals  may  be  raised  in  the  laboratory. 
The  committee  in  charge  of  cultures  may  Lr<»  to  a  pond    Bn  ik  the 
ice  if  it  is  winter.)  and  secure  some  water  weeds,  particularly  th< 
which  are  covered  with  a  great  deal  of  slime.     Place  them  in  some 
glass  pans  and  let  stand  for  some  days,  when  amebas  may  be  found 
on  the  sides  of  the  glass  and  in  the  sediment  at  the  bottom.     !'  will 
do  no  harm  if  the  culture  gets  scum  on  it-  surfai         Mak<  ral 
cultures,  each  different  in  some  details  from  the  other       The  ame 
on  the  sides  of  the  glass  should  be  taken  off  by  rubbing  the  I 
along  the  glass  and  transferring  the  material  which  it  coll< 
microscope  slide.     If  any  are  found,  they  should  be  studied 

as  they  may  be  gone  in  a  day  or  two.  Note  how  they  mo 
and  avoid  objects  in  their  path.  Can  the  nucleus  be  found? 
vacuole  be  found?     How  are  the  pseudopodia  put  out  and  .  in? 

Draw  an  ameba  in  several  shape-  as  it  ■.         Jong. 

If  amebas  can  not  be  obtained  by  the  method  described 
had  alive  from  the  various  dealers,  and  should  l»< 
They  may  be  had  permanently  mounted  <>n  mi< 

130.  Paramecia.  These  animals  will  be  found,  ith 
many  other  protozoans,  in  the  cultures  described  aboi  tam- 
ing  amebas.     The   hay   infusion   culture    is    the   si 


4O  PROJECTS   AND   EXPERIMENTS   IN  BIOLOGY 

should  be  made,  and  a  little  water  from  a  pond  or  from  the  ameba 
cultures  should  be  added  to  inoculate  it.  The  hay  should  be  chopped 
fine,  and  placed  in  water  about  two  weeks  before  the  protozoans  are 
to  be  studied.  A  scum  of  bacteria  will  rise  to  the  surface.  This  is 
the  food  on  which  the  paramecia  lives. 

Place  some  of  the  scum  on  a  slide  and  note  their  movements. 
We  have  referred  to  the  avoiding  reaction  before.  Can  their  cilia 
be  seen?  Note  whether  they  go  backwards  as  much  as  forwards. 
How  rigid  is  the  shape  of  their  bodies?  Can  the  nucleus  be  found? 
The  oral  groove?  A  vacuole?  Watch  one  gather  food.  If  they 
go  too  fast  to  be  seen  well,  they  may  be  entangled  in  some  fibers  of 
cotton  if  it  is  placed  on  the  slide,  or  as  the  water  dries  they  will 
become  less  active.  A  thin  solution  of  gelatin  will  be  of  value  also. 
Run  it  under  the  cover  glass.  As  the  protozoans  swim  into  it,  their 
motion  is  impeded. 

131.  Other  protozoans  will  be  found  in  the  cultures  with  the 
amebas  and  the  paramecia.  Observe  them,  try  to  learn  their 
names,  and  make  some  sketches  of  some  of  them.  You  will  find 
various  worms  and  crustaceans  also.  For  the  identification  of  the 
forms  which  you  find  see  The  Protozoa  0}  Iowa,  Edmondson,  Daven- 
port Academy  of  Sciences;  and  Life  of  Inland  Waters,  Needham  and 
Lloyd,  Comstock  Pub.  Co.  The  identification  and  enumeration  of 
those  found  will  make  an  interesting  project  for  an  individual  or 
group. 

132.  Questions. — What  is  a  balanced  aquarium?  Is  a  hay 
infusion  balanced  in  this  sense?  Why  does  the  culture  die  out? 
How  long  are  the  protozoans  abundant  in  the  culture?  Would  they 
become  numerous  again  if  more  hay  were  added?  How  does  a  hay 
infusion  differ  from  a  balanced  aquarium? 

133.  Division. — When  the  culture  is  at  its  best,  you  should  be 
able  to  find  specimens  which  are  dividing.  Look  for  them.  They 
will  seem  to  be  double  individuals.  Are  they  just  as  active  as  the 
ones  which  are  not  dividing?  Only  a  few  people  have  seen  the 
ameba  divide,  but  hundreds  of  paramecia  may  be  seen  dividing  in  a 
good  culture.  They  are  about  one  half  as  large  as  others  and  are 
attached  end  to  end.  How  long  does  it  require  to  complete  the 
process  of  division?     See  Figs.  144,  145,  Atwood's  Biology. 


ALCE,   MASSES,    AND    ll  RNS 

134.  Conjugation. — In  tin-  same  culture  where  the 

growing  rapidly  you  should  be  able  to  find  a  few  individuals  which 
are  conjugating.  These  specimens  are  attached  by  their  sides  ;m«i 
can  be  distinguished  easily  from  those  which  arc-  dividin] 

135.  Draw  diagrams  of  specimens  which  are  dividing  and  als 
which  are  conjugating.     A  good  description  of  the  conjugation 
paramecia  may  be  found  in  Hegner's  College  Zoology. 

136.  Notebook  Work.-- Write  a  description  of  the  most  successful 
methods  of  making  a  culture  for  paramecia.  How  many  days  after 
preparing  the  culture  did  the  paramecia  appear?  How  long  do  they 
stay?  How  many  days  is  the  culture  covered  with  scum?  On 
what  do  the  paramecia  feed?  Describe  the  process  of  locomotion. 
Describe  any  other  interesting  things  which  were  seen  in  theculturt 
Consult  references  and  describe  division  and  conjugation. 

137.  Plasmodium  malaria  is  the  cause  of  chills  and  fevers. 
Atwood's  Biology,  p.  176  and  various  other  texts  and  write  a  descrip- 
tion of  its  life  history.     Accompany  your  description  with  diagrams. 

17.  LESSONS  WITH  ALGJE,  MOSSES,  AND  FERNS 

References 

Practical  Botany,  Bergen  and  Caldwell,  Ginu  &  Co. 
Fundamentals  of  Botany,  Gager,  1'.  Blakis ton's  Son  <S:  Co. 
General  Botany,  Densmorc,  (linn  &  Co. 
Civic  and  Economic  Biology,  Atwood,  Studies  26,  27,  and 

138.  Gleocapsa  is  one  of  the  simplest  of  the  blue-green  alg 
It  may  be  found  in  greenhouses,  in  moist  places,  and  in  cultures  of 

algae  which  are  kept  in  the  laboratory,  or  it  may  be  had  from  dealer-. 
Place  some  cells  under  the  microscope.  Note  the  gelatinous  envel- 
opes which  surround  each  cell,  and  how  they  may  be  within  each 
other  if   the   specimens   are   multiplying   fast.       Vs    th(  .    tin- 

older  walls  become  dissolved  away.     Draw  a  single  cell. 
see  a  nucleus?     Should  then-  be  one?     Draw  a  group  lis. 

139.  Pleurococcus  may  be  found  on  the  north  side  oi  tree  truni 
fence  posts,  and   the  like.      Ii    is  very  abundant   and   IS  one  of  the 
simplest  of  the  green  algae.      It   has  a  nucleus  and  a  chloroplast   in 
which  the  chlorophyll  is  held,     [s  there  a  gelatinous  envelope  around 


48  PROJECTS   AND   EXPERIMENTS   IN  BIOLOGY 

the  cells  as  in  gleocapsa?     Draw  a  single  cell  and  label  the  parts. 
Draw  a  group  to  show  division. 

140.  Spirogyra  is  an  advanced  type  of  the  green  algae.  Illustra- 
tions of  it  arc  printed  in  nearly  all  of  the  books  on  biology  and 
botany.  See  At  wood,  Fig.  149  and  184.  If  some  material  was  col- 
lected in  the  fall  and  preserved  in  formalin,  it  will  probably  show 
the  stages  of  conjugation.  Examine  the  cells  of  the  filaments  under 
the  microscope.  Note  the  shape  of  the  cells  and  the  filaments. 
Find  the  bands  of  chlorophyll  which  wind  in  spirals  through  the 
cells.  Find  the  pyrenoids  as  dense  areas  along  the  bands.  Run  a 
drop  of  iodine  solution  over  the  preparation  on  the  microscope  slide, 
and  after  a  few  moments,  the  nucleus  will  be  visible.  The  number 
of  bands  of  chlorophyll  varies  in  different  species  of  spirogyra.  How 
many  bands  has  your  specimen?  See  some  of  the  illustrations  in 
texts,  make  drawings  of  the  stages  of  conjugation  in  spirogyra,  and 
write  a  description  of  the  process. 

141.  If  time  permits  and  material  is  available,  ulothrix  and 
vaucheria  may  be  studied.  Directions  for  their  examination  will  be 
found  in  Laboratory  and  Field  Manual  of  Botany,  Bergen  and  Davis; 
and  A  Laboratory  Guide  for  General  Botany,  Gager. 

142.  Make  a  table  listing  the  advantages  which  pleurococcus  has 
over  gleocapsa.  Show  the  advantages  which  spirogyra  has  over 
pleurococcus.  What  advantages  has  vaucheria  over  spirogyra. 
Understand  from  this  table  that  there  is  an  ascending  complexity 
in  the  algae.  Copy  one  of  the  best  tables  on  the  board  and  discuss 
it  in  class. 

143.  Moss  Plants. — It  will  be  difficult  to  make  a  set  of  directions 
for  the  study  of  the  moss  which  will  be  suited  to  many  schools. 
The  following  are  only  suggestions. 

144.  Class  Work. — Pictures  of  mosses  may  be  passed  around  the 
class.  Material  showing  sexes,  and  sporophytes  may  also  be 
observed.  Discussions  of  the  various  habitats  of  mosses  may  be 
valuable.  Slides  showing  the  protonema,  antheridia,  and  arche- 
gonia  may  be  thrown  on  the  screen  with  a  lantern. 

145.  Notebook  Work. — A  diagram  of  the  life  history  of  mosses 
may  be  put  in  the  notebook.  Write  a  description  of  it.  These 
may  be  corrected  by  the  archives  committee  and  the  instructor. 


THE    IMM      i  ii  I 


146.  The  fern  may  be  studied  as  the  moss  alxr        [t  ha 
stems,  and  leaves.     These  may  be  studied,  by  making  dra 

them   or   their  parts.     The  spores,   spore   ca         antheridia,  and 
archegonia  must  be  seen  under  the  mi(  ros<  ope  U<  ause  of  their  small 

size.     Permanent  slides  may  be  had  from  the  dealei 

147.  Notebook  Work.     Write  up  the  life  history  of  the  fern  fi 
the  material  which  you  have  in  the  laboratory  and  the  informati 
which  you  get  from  Study  28,  Atwood's  Biology.     It'  a  more  com- 
plete and  detailed  study  of  the  fern   is  to  be  made,  I 
laboratory  manual,  and   Bergen  and    Davis  also.     Part  -  of   tl 
directions  may  be  copied  on  the  board. 

148.  Project. — Try  to  raise  some  mosses  and  ferns  from  their 
spores  in  the  laboratory.     Place  the  spores  on  moisl  -<»il  in  . 
pans  and  keep  them  covered  with  glass  plates  <»r  bell  jar-  so  tl 
will  not  get  dry.     They  must  have  a   moderate  amount   of  bright 
light.     Have  patience  for  they  grow  slowly. 

149.  Make  a  table  listing  the  advantages  of  tin-  moss  over  the 
algae.     Make    another,    or   add    to    the    -aim-   one.    and    -how    tin- 
advantages  of  the  fern  over  the  moss.     Compare  the  tables  in  dis<  u 
sion  in  the  class  and  write  the  best  li-t  on  the  board. 


18.  THE  LIFE  HISTORY  OF  THE  PINE  TREE 

References 

Civic  (Did  Economic  Biology,  Atwood,  Study 

The  botanies  listed  for  the  previous  study. 

Principles  of  Botany,  Bergen  and  Davis,  manual  and  text,  Ginn  8  ' 

Text-Book  of  Botany,  Coulter,  American  Book  Co. 

150.   Field  Trip.      If  there  are  any  pine  tree-  near  the  School,  they 

should  be  studied  on  a  held  trip.     Compare  the  tri  thers 

in  size.     How  are  their  branches  arranged?     Ire  the 
the  year  around?     How  man)  ins  do  the  needles  stay  <  1 1 

are  the  needles  arranged  in  their  clusters       I        rminal  buds  foron 
at  the  end  of  each  season's  growth?     About  how  much  d 

tree  grow  each  year? 

1 


50  PROJECTS    AND    EXPERIMENTS    IN   BIOLOGY 

Do  you  find  any  resin  on  the  bark?  Do  pines  have  sap  or  resin 
in  their  growing  tissues?  Can  you  find  any  cones?  Are  they  all 
alike?  How  long  does  a  cone  stay  on  the  tree.  Bring  some  of  the 
cones  to  the  laboratory.     Shake  some  of  the  seeds  out  (?). 

151.  Study  Sections  of  Pine  Wood. — How  are  their  rings  formed? 
Use  a  lens  and  see  if  there  are  any  sap  ducts?  Can  you  find  the 
resin  duels.     Is  pine  lumber  hard  or  soft  wood?     What  is  it  used  for? 

152.  Laboratory  Study. — See  as  many  of  the  parts  of  the  cones  of 
pines  as  you  can  (p.  196,  Atwood's  Biology;  also  Chap.  XXVI, 
Gager's  Fundamentals  of  Botany)  and  make  drawings  of  some. 

153.  Notebook  Work. — Write  up  the  life  history  of  the 
pine.  See  the  two  references  mentioned  above  and  also  Bergen  and 
Davis,  Principles  of  Botany.  This  is  a  difficult  study.  Give  it  your 
most  careful  attention,  and  much  time. 

154.  Museum  Committee  Project. — Make  a  collection  of  the 
various  kinds  of  conifer  leaves.  Mount  them  on  sheets  on  botanical 
mounting  paper  and  label  properly.  Show  them  to  the  class  and 
save  for  future  classes. 


19.  THE  PARTS  AND  FUNCTIONS  OF  THE  FLOWER 

References 

Civic  and  Economic  Biology,  Atwood,  Studies  30  and  31. 
Botany  of  Plant  Crops,  Robbins,  P.  Blakiston's  Son  &  Co. 
General  Science,  Bowden,  Chap.  XXIII. 

It  is  unfortunate  that  this  study  comes  in  the  winter  when  flowers 
can  not  be  had  from  the  out-of-doors,  but  in  these  days  of  green 
houses  and  steam  heat,  they  can  be  had  at  this  season  from  indoor 
plants,  and  there  are  many  things  which  urgent  necessity  compels 
us  to  study  in  the  fall  and  spring;  therefore  this  study  has  been  put 
in  the  winter  in  Atwood's  Civic  and  Economic  Biology. 

155.  Secure  flowers  of  various  types  from  such  sources  as  are  in 
the  school  or  the  community  and  make  a  study  of  petals, 
sepals,  stamens,  and  pistils.  Note  also  color,  perfume,  nectar,  and 
arrangement. 


i  in     i  i  <»\\  i;k 


5 


— corolla 

tube 
-  -sterna 

stamen 


156.  Draw  a  flower  from  a  monocotyledonous  and  hum  a  dicotyle- 
donous plant.  How  do  they  compare  as  to  the  above  mentioned 
features?     It   is   not    necessary  that  each  student  draw  the 

flower,  and  if  time  permits,  several  should  be  drawn.     I  ,  in 

Atwood's  Biology  will  he  of  assistance  in  labeling.     See  also  similar 

figures  in  other  texts. 

157.  Notebook  Work.     Make  a  table  of  the  various  kinds  of 
inflorescences  and  assign  each  flower  in  the  laboratory  to  it-  proj 
place  in  the  table.     Make  a  list  of  the  various  ways  which  plant- 
have  of  obtaining   better  cross  pollination,   and    li-t    an   example 
opposite  each  method  listed.     Make 
a  list  of  the  most  important  plant 
families   and   name   the  chief  char- 
acteristics of  each.    Name  one  or  two 
plants  in  each  family.     These  tables 
may  be  made  out  as  a  class  project 
with    the    instructor    as    chairman. 
As  the  flowers  are  discussed  samples 
should   be  passed  around   the  class. 
When  these  are  not  available,  pic- 
tures must  suffice. 

158.  Germination  of  pollen  is 
easily  accomplished  if  the  grains  are 
placed  in  a  solution  of  sugar  of  a 
strength  of  from  10  to  jo  per  cent. 
They  should  be  viewed  with  a  com- 
pound microscope.  Will  old  pollen 
germinate?  See  Atwood's  Biology, 
Figs.   166  and  187. 

159.  A  flower  calendar  may  be  kept  from  year  to  year.     When 
spring  comes,  let    the  students  bring  to  the  laboratoi  Olples  <•! 
the  first  flowers  of  each  kind  which  are  found  and  the  da!  their 
first  appearance  may  be  recorded.     Are  the  early  flower  ua! 
or  perennials. 

160.  A  similar  calendar  for  the  trees  to  compare  the  times  wl 
their  first  leaves  appear  may  be  made  also. 


-ovary 
-ca\u 


Pig.  29. 
show  tin-  names  and 
the  parts 

an  .  '/>  I'ltf 


■ 


52 


PROJECTS    AND    EXPERIMENTS    IN   BIOLOGY 


20.  CELL  DIVISION 

References 

Civic  and  Economic  Biology,  At  wood,  Study  32. 
Text-book  of  Zoology,  Galloway,  P.  Blakiston's  Son  &  Co. 
Plant  Anatomy,  Stevens,  P.  Blakiston's  Son  &  Co. 
Being  Will  Born,  Guyer,  Bobbs-Merrill  Co. 

161.  Cell  Growth. — By  using  the  microscope,  examine  cells  of 
yeast,  pleurococcus,  spirogyra  or  some  other  single  celled  plant. 
Are  the  cells  of  the  same  size?  Do  you  think  that  the  larger  cells 
were  once  smaller  than  they  are  now?     Do  cells  grow? 


- ! 

'    I    • 

V 


B 


- 


i5\ 


m 


=j) 


D 


r 

'"'■■""'     ■■' ) 

■    ■  - 

- : . — ^ 

G  H  I 

Fig.  30. — Diagram  to  show  cell  division  (mitosis)  in  plant  cells.      {Fundamentals 

of  Botany,  Gager.) 


162.  Cell  Division. — Examine  the  same  cells  as  above  and  note 
those  which  have  divided.  Why  has  the  spirogyra  cell  division 
resulted  in  the  production  of  a  filament  and  the  division  in  pleuro- 
coccus  a  group  of  cells.     Are  all  divisions  in  the  same  direction? 


I  I ."\\  i  RING    PLAN  I  - 


163.  Cell  Budding.-  Examine  yeasl    cells  and   note   how   tl 
multiply  by  budding. 

164.  Draw  types  of  the  specimens  which  have  been  studied. 

165.  Chromosome  changes  in  cell  division  may  be  shown  by 
using  permanent  mounts  of  the  root  tips  of  the  onion  <>r  some  lily. 
These  slides  may  be  had  from  the  dealers.  Find  cells  which  illus- 
trate all  of  the  stages  of  division  shown  in  the  illustration.  The 
illustration  in  Atwood's  Biology  is  of  a  typical  animal  cell.  I 
shown  here  is  of  a  typical  plant  cell.  Plant  cells  have  no  centro- 
somes.  Write  a  description  of  cell  division  describing  all  of  tin- 
changes  which  take  place  in  the  chromosome. 

21.  THE  LIFE  HISTORY  OF  FLOWERING  PLANTS 

References 

General  Botany,  Densmore,  Ginn  &  Co. 

Civic  and  Economic  Biology,  At  wood,  Studies  32  and   $$. 

170.  This  study  must  be  made  from  microscope  slides  or  from 
lantern  slides,  unless  the  class  and  instructor  are  content  to  make  it 
from  illustrations  in  books.  It  is  a  difficult  study  for  high  school 
students,  but  it  is  valuable  as  completing  the  outline  of  the  evolution 
of  plants.  It  is  interesting  to  know  how  the  flowering  plant  came 
to  be  what  it  is.  This  study  is  also  of  value  in  understanding  tin- 
subjects  of  heredity  and  plant  breeding.  If  it  wen-  spring,  it  would 
be  valuable  to  make  a  field  trip  and  observe  the  great  variety  of 
flowering  plants,  and  it  should  be  understood  that  it  includes 
and  trees  which  do  not  have  conspicuous  flowers.  Understand  also 
that  the  sporophyte  and  the  grains  of  pollen  an-  the  only  pha 
the  life  history  of  flowering  plants  which  ran  be  observed  naturally. 
All  else  must  be  especially  prepared.      Read  Gager  a::  gen  and 

Davis  for  advanced  references. 

Directions  for  the  study  of  the  microscope  slides  which  may  be 
at  hand  will  have  to  be  written  up  by  the  instrw  tor  a-  ii  varies  in 
different  schools.     Some    students    may    assist    by    copying    the 
directions    on    the    board.     See    Laboratory    and    Field    I 
Densmore. 


54 


PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 


Fig.  31. — Types  of  pollen  grains  as  seen  under  the  microscope.  A,  Typha 
lati folia;  B,  corn;  C,  Ambrosia  elalior;  D,  Philadelphia  lily;  E,  pine;  F,  buttercup; 
G,  blue  beech;  H,  Althaea  rosea,  rose-mallow;  i\  primrose.  {Pharmaceutical 
Botany,  Youngken.) 


FRUITS     WD    SI  ID    DISTRIB1    I  I'  '\ 


>.  >. 


171.  Pollen  gains  may  be  viewed  under  the  microscope       'II 
arc  of  a  great  variety  of  forms.     See  the  illustration.     If  they  w 

not  germinated  in  sugar  solution  in  a  previous  Study,  this  in- 

done  now.     The  pollen  tube  is  a  male  gametophyte.     Sketch  some 
pollen  grains  and  later,  some  which  have  germinated. 


22.  FRUITS  AND  SEED  DISTRIBUTION 

References 

Botany  for  Colleges,  Ganong,  Macmillan  &  Co. 
Practical  Botany,  Bergen  and  Caldwell,  Ginn  &  Co. 
Civic  and  Economic  Biology,  At  wood.  Studies  ,^4  and  35. 
Interesting  Neighbors,  Jenkins,  P.  Blakiston's  Son  &  Co. 

Fortunately,  most  all  fruits  may  be  preserved  easily  in 
the  museum  either  in  the  dried  form  or  in  formalin.  The  museum 
committee  will  get  ready  as  many  fruits  and  seeds  as  is  1  onvenient 
for  the  study.  Write  out  the  table,  which  appears  in  four  columns 
on  p.  233  of  Atwood's  Biology,  in  one  column.  \<»w  write  opposite 
its  proper  classification  the  name  of  each  fruit  which  you  have  to 
study. 

172.  Draw  various  ones  of  the  fruits  which   may   be  sele<  ted. 
Label  their  parts  carefully  and  note  on  the  drawing  to  which  cla 
they  belong.     Do  not  include  any  seeds  in  the  drawings.     They  are 
to  be  studied  later.     Be   able   to  state  clearly   the  difference   1 
tween  fruits  and  seeds.     Also,  be  careful  not  to  (  lassify  any  fruit- 
seeds. 

173.  Make  a  table  of  the  methods  of  distribution  of  fruits  in 
nature.     Now  go  over  the  fruits  which  you  have  Listed  in  the  table 
classification  and  list  them  according  to  their  methods  of  distribution. 

174.  Make  a  table  of  the  method-  of  distribution  of  see  N  and 
fill  it  out  as  you  did  the  one  for  the  distribution  <>\  fruits. 
which  are  carried  by  the  wind  may  be  released  in  t; 

practical  demons!  ral  ion  of  how  they  are  a  tit  t  ted  by  a  1  m  renl  ol  air. 

After  the  study  is  made  the  museum  committee  will  collect  the 
fruits  and  seeds  and  save  them  for  the  next  1  lass. 


56 


PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 


1 


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312 


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FRUITS    AM)    SEED    DISTRD31    W 


175.  Saturday  Field  Project.-  A  party  of  student  for 

a  tramp  in   the  fields  and  woods.     Make  a  collection  of  th< 
and  fruits  which  are  still  on   the   weed   stems,  bush 
Make  a  collection  of  such  seeds  and  burs  as  stick  to  your  clothii 
If  there  is  a  dog  along  with  the  party,  his  fur  should  tx 
also.     Bring  the  material  before  the  class  and  di  what   you 

have  learned. 

position  of 

epicarp 

mesocarp 
endocarp 

stone' 


-I- testa 

otJedons 
of  embryo 

-  calyx 


Fig.  33. — Section  of  a  young  cherry  to  show  tin-  struct 

(  Botany  o/  (  'top  Plam 


176.  Questions.     How  many  of  the  fruits  and  berri 
collected  are  eaten  by  lards?     Would  they  Ik-  more  apt  to  tx 
if  they  remained  on  the  bush  than  if  they  fell  on  the  ground?     Why 
are  unripe  fruits  green  in  color  and  sour  or  bitter  in  Is  \\  In 

ripe'fruits  sweet  and  bright  colored?     Make  a  li-l  of  tin-  ways  whi 
green  fruits  have  of  protecting  themselves  and  amples 


58 


PROJECTS    AND   EXPEKIMENTS    IN   BIOLOGY 


FRUITS     \\I>    S]  I  I)    DIS1  kll;r  I  [( 


each.     How  many  kinds  of  apples  do  you  I. now  by  sight?     M 

list  of  those  which  you  know.     I ).» the  same  for  other  fruits,     I  >o  you 


Fig.  35. —  Wink't^l  st  ids  which  are  distributed  by  the  wind.     F 
above — linden,  ailanthus,  :m<l   clematis;  below — maple  and  elm. 
Neighbors,  Jenkins.  I 

know  of  any  fruit  which  has  no  special  method  of  facilitating 
distribution? 


6o  PROJECTS    AND    EXPERIMENTS    IN   BIOLOGY 


23.  STUDIES  IN  PLAOT  PROPAGATION 

References 

Civic  and  Economic  Biology,  Atwood,  Study  36. 

Botany  of  Plan!  Crops,  Robbins,  P.  Blakiston's  Son  &  Co. 

Experiments  with  Plants,  Osterhout,  Macmillan  &  Co. 

177.  Review. — If  bread  mold  was  grown  in  a  previous  experiment, 
it  will  not  be  necessary  to  do  it  again.  It  should  be  recalled  that 
it  is  a  kind  of  plant  which  is  propagated  by  spores.  What  other 
kinds  of  plants  are  propagated  by  spores?  What  advantages  has 
spore  production  over  seeds  as  a  method  of  reproduction? 

178.  If  ferns  or  mosses  were  grown  from  spores  in  a  previous  study, 
they  may  be  shown  to  the  class  at  this  time  also. 

179.  Propagation  Projects. — Plants  may  be  propagated  from 
spores,  roots,  underground  stems,  bulbs,  stems,  leaves,  and  seeds. 
Each  student  should  choose  a  method  of  propagation  and  attempt  to 
prepare  for  the  rest  of  the  class  a  demonstration  of  some  type  of 
plant  propagation.  A  record  should  be  kept  of  the  selections,  and 
they  should  be  reviewed  by  the  instructor  to  avoid  trying  something 
which  can  not  be  done.  As  they  are  ready  the  results  should  be 
shown  to  the  class.  A  considerable  number  and  variety  of  seeds 
should  be  planted.  They  are  to  be  used  in  the  following  studies, 
and  should  be  ready  when  that  work  is  taken  up. 

The  sweet  potato  and  dahlia  are  good  roots  to  illustrate  propaga- 
tion by  fleshy  roots.  Tubers,  bulbs,  corms,  and  rhizomes  may  be 
had  from  the  seed  stores.  Apple,  willow,  Cottonwood,  and  gera- 
nium are  good  examples  for  stem  propagation.  But  few  plants  are 
propagated  by  their  leaves.  The  best  examples  are  the  walking 
fern,  various  begonias,  and  the  live-for-ever  which  belongs  to  the 
genus  Bryophyllum. 

180.  Grafting  Practice. — Secure  some  branches  of  willow,  or 
other  soft  wood,  grafting  wax,  raffia,  and  some  sharp  knives  or 
scalpels.  Let  each  student  in  the  class  make  a  graft  after  one  of  the 
methods  shown  in  the  illustration.  Name  the  different  kinds  of 
grafts  and  learn  for  what  use  each  is  the  best  adapted.  Why  is 
grafting  necessary  in  the  fruit  growing  industry? 


PI  \\T    PROPAGATION 


Pig.  36. — Various  methods  of  grafting.     Prom  the 
Leaflets.     1,   Root  grafting;   2,  clefl   grafting;    {, 

a,  scion;  b,  stock;  c,  the  two  united;  </  and  «•.  the 
Gagcr.) 


62 


PROJECTS   AND   EXPERIMENTS   IN  BIOLOGY 


181.  Notebook  Work. — List  in  a  table  all  of  the  different  methods 
by  which  plants  may  be  propagated,  and  write  opposite  each  method 
the  name  of  a  plant  which  may  be  propagated  in  that  way. 


24.  SEEDS  AND  SEED  GERMINATION 

References 

Civic  and  Economic  Biology,  Atwood,  Studies  37  and  38. 
Experiments  with  Plants,  Osterhout,  Macmillan  &  Co. 
Manual  of  Experimental  Botany,  Payne,  American  Book  Co. 

182.  Notebook  Work. — Consult  Fig.  212  and  fill  out  the  table 
on  p.  249  of  Atwood's  Biology.  The  museum  committee  should 
show  the  class  such  samples  and  specimens  as  they  have  which  have 
a  bearing  on  this  problem. 

183.  .A  Grain  of  Corn. — The  materials  required  for  this  study 
were  probably  prepared  in  the  previous  exercises  on  plant  propaga- 


yhom\) 
endosperm 


Fig.  37. — Sections  of  corn  grains.      A,  Dent  corn;  C,  flint  corn,  both  lengthwise 
sections.     B,  Cross  section  of  dent  corn.      (Botany  of  Crop  Plants,  Robbins.) 

tion,  as  were  those  for  the  ones  which  follow.  Soaked  corn  grains, 
and  others  in  varying  stages  of  development,  should  be  observed. 
Consult  Fig.  213  in  Atwood's  Biology;  Fig.  22  in  Payne's  Botany; 
Chaps.  VI  and  VII  in  Moon's  Biology;  pp.  56-59  in  Hunter's 
Biology;  and  Chap.  VIII  in  Gruenberg's  Biology  as  references  on 
this  exercise  and  the  ones  which  follow. 


SEEDS    AM)    SEED    GERMINA1  I 


In  the  corn  seed  the  endosperm  has  doI   I 
cotyledons.     Test    the    endosperm    for    starch. 
germinating    seed    for   glucose.     Test    the   dry 
seed  for  glucose.     Test  the  embryo  for  protein. 
There  is  considerable  oil  in  corn  also. 

Draw  three  or  four  germinating  corn  seeds  to 
show  the  stages  of  the  process.  Identify  the 
primary  root,  the  secondary  roots,  and  the  root 
hairs.  Note  that  the  primary  and  secondary 
roots  grow  in  opposite  directions.  Find  tin- 
plumule  sheath  which  surrounds  the  shoot  but 
does  not  get  above  the  soil.  Note  that  there 
is  but  one  blade  when  the  plant  breaks  through 
the  soil.  This  is  followed  by  others  in  an 
alternating  arrangement.  Are  they  ever  paired? 
What  becomes  of  the  corn  seed  as  the  plant 
grows? 

184.  A  Bean  Seed. — The  materials  were  prob- 
ably prepared  in  the  studies  on  plant  propagation. 
Soaked  seeds  and  some  in  varying  stages  of  de- 
velopment should  be  available.  Consult  the 
references  given  above  for  the  study  of  the 
corn  seed,  especially  Atwood,  P.  25c  and  Fig. 
215.     Study  the  bean  seed  as  you  did  corn. 

185.  The  Pea  Seed. — Proceed  as  directed  for 
the  study  of  corn  and  the  bean.  The  reason  for 
adding  the  pea  seed  after  studying  the  bran  is 
that  the  pea  leaves  its  cotyledons  in  the  soil, 
and  the  bean  lifts  them  into  the  air.  Otherwise 
the  bean  and  pea  seedlings  are  very  much  alike 
in  their  germination. 

186.  The  Squash  Seed.  Consult  Fig.  216  in 
Atwood's  Biology  and  study  squash  seedlings  as 
directed  above  for  the  others. 

187.  Topic-  Write  a  short  paper  setting  for 
and  dissimilarities  of  the  four  seedlings  which  w 
directed  above. 


ali-orbed    by    the 
1  est     !  In-     entire 


Pk 
of    making    ;t    w 
culture  intf 

..  »w  thi  '  the 

endosperm 

M  ;i  If 

cult- 

the     cotyl 
endosperm 

one  '■«•     A 

Solllt 

the      t 

th  the  similarities 
e  have  studied 


64  PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 

Additional  and  more  complete  directions  for  the  study  of  seeds  and  seedlings 
may  be  found  in  Bergen  and  Davis,  Laboratory  and  Field  Manual  of  Botany, 
beginning  on  p.  17.  Also  Gager,  A  Laboratory  Guide  for  General  Botany, 
p.  16. 

188.  Projects. — The  following  projects  should  be  chosen  by 
various  students  who  will  work  them  out  and  present  the  solution  to 
the  class.  Failures  should  be  brought  before  the  class  as  well  as 
successes.  It  often  happens  that  more  can  be  learned  from  a  failure 
than  from  a  success.  Do  not  bother  the  instructor  for  advice. 
Solve  your  own  problem.  Use  all  of  the  references  which  may  be 
available. 

a.  Will  seeds  germinate  without  water,  even  if  all  other  conditions 
are  favorable? 

b.  Without  air? 

c.  Without  soil? 

d.  Without  light? 

c.  At  a  low  temperature?  How  low?  Does  it  vary  for  different 
seeds? 

/.  Does  soaking  seeds  before  they  are  planted  cause  them  to  come 
up  more  quickly? 

g.  Must  squash  seeds  be  dried  after  they  are  taken  out  of  the 
squash  before  they  will  grow? 

h.  Will  seeds  germinate  in  strong  salt  water?     Why? 

i.  Fill  a  small  flower  pot  with  corn  grains.  Fasten  the  saucer 
on  the  top.  Make  it  tight  by  binding  it  on  with  wire.  Soak  it  in 
water,  then  take  it  out  and  keep  it  in  a  warm,  moist  place.  Soak  it  in 
water  once  each  day.  Why  must  seeds  exert  force  in  germinating? 
What  is  the  source  of  this  energy? 

j.  Illustrate  geotropism  of  seedlings. 

k.  Illustrate  hydrotropism  of  roots  of  seedlings. 

/.  Illustrate  phototropism  with  a  seedling. 

m.  Plant  some  large  and  small  seeds  in  the  same  dish.  Which 
grow  the  faster?  What  is  the  advantage  of  the  large  amount  of 
food  in  the  larger  seed? 

;/.  Remove  the  cotyledons  of  various  seedlings  just  as  they  sprout 
and  compare  them  with  others  which  have  been  left  alone.  Do 
seedlings  get  food  from  their  cotyledons? 


LIFE    HISTORIES    OF    WIM  \i 

The  reason  for  presenting  the  problems  mentioned  above  as  indn  idual  pro  I 
is  that  this  method  is  more  effi<  ienl  as  to  effort,  time,  and  3]  1  1       It  would  not 
be  possible  for  each  student  to  solve  each  problem  in  an  elementary  in 

biology. 

189.  Glucose  may  be  tested  for  in  various  kind-  of  seeds  which 
have  germinated.  Test  the  same  seeds  before  they  have  started 
to  germinate.     Did  you  get  so  strong  a  test  ?     Explain. 

190.  Problem. — At  what  depth  do  torn  seeds  germinate  !>• 
Plant  grains  of  corn  at  various  depths  against  the  sides  of  a  gla 
vessel,  and  when  the  ones  which  have  germinated  in  the  best  order 
and  way  are  ready  show  the  vessel  with  its  seedlings  to  the  class. 
How  deep  should  corn  be  planted?     Should  all  seeds  be  planted  at 
this  depth?     Why  the  difference? 


25.  LIFE  HISTORIES  OF  ANIMALS 

References 

Civic  and  Economic  Biology,  At  wood,  Studies  39,  40,  and  41. 

All  of  the  zoologies  and  biologies  deal  with  this  subje<  t . 

Secure  the  embryological  models  of  amphioxus,  frog,  and  chit  k  from  the  de  il 

in  biological  supplies. 

191.  The  Fish. — Developing  eggs  of  various  species  of  fish  may 
be  had  from  the  U.  S.  Bureau  of  Fisheries  or  some  of  the  statioi 
and  from  dealers  in  biological  supplies.     For  reference  Kell< 
and   Doan's   Zoology;   and  Civic  Biology  by  Hodge  and   I  >n, 
Chap.  XXVII. 

192.  Draw  a  series  of  developing  eggs  to  show  the  pr<  from 
an  egg  to  a  fish. 

193.  The  Frog.     If  frogs'  eggs  were  collected  and  preserved  in 
formalin  the  previous  spring,  they  may  be  studied  under  the  mien 
scope.     Try  to  find  two,  four,  and  eight  cell  stages  in  tl 

of  the  egg.     Eggs  in  various  stages  of  development  may  be  had  from 
the  dealers  in  Biological  suppli< 

194.  Draw  the  stages  of  cleavage  of  the  frog        g  whi<  h  you  find. 


66  PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 

195.  The  tadpole  may  be  studied  from  material  which  was  pre- 
served from  last  spring's  catch,  purchased  from  dealers,  or  from 
charts.  See  Fig.  224  in  Atwood's  Biology.  Before  the  frog's  egg 
hatches  the  tadpole  can  be  seen  to  move  within  the  white  of  the  egg. 
When  it  comes  out,  it  has  no  mouth  but  clings  to  objects  with  its 
sucker.  It  is  black  and  is  covered  with  cilia.  Find  a  stage  with 
externa]  gills.  As  these  are  withdrawn,  the  internal  ones  appear. 
Which  legs  appear  first?  How  is  the  tail  disposed  of?  What  does 
the  young  tadpole  eat?  When  does  it  first  begin  to  breathe? 
When  are  frog's  and  toad's  eggs  laid?  When  do  they  develop  into 
frogs  and  leave  the  water? 

196.  Draw  a  series  of  tadpoles  to  show  the  progress  from  an 
embryo  to  the  fully  formed  frog  from  actual  specimens  or  from 
models. 

197.  The  Bird. — Excellent  wax  models  of  the  stages  of  develop- 
ment of  the  chicken's  egg  may  be  had  from  the  dealers.  Eggs 
may  be  incubated  in  an  incubator  and  the  living  embryos  may  be 
seen.  Chicken,  pigeon,  and  turtle  embryos  which  have  been 
mounted  permanently  on  microscope  slides  may  also  be  purchased. 
Consult  the  illustrations  in  Study  40  of  Atwood's  Biology. 

198.  Draw  a  series  of  chick  embryos  to  show  development  from 
the  egg  to  hatching.  Label  as  completely  as  possible,  but  do  not 
expect  to  know  all  about  bird  embryology  in  this  brief  study.  If 
you  get  the  general  trend,  it  will  be  sufficient. 

199.  The  Mammal. — It  will  be  more  profitable,  in  the  majority 
of  schools,  to  spend  more  time  on  the  development  of  the  chick  and 
to  leave  out  the  study  of  mammalian  embryos.  Pig  embryos  are 
the  most  frequently  studied.  They  may  be  had  from  the  dealers, 
either  entire  or  sectioned  and  mounted  on  microscope  slides.  It  may 
be  profitable  to  study,  observe,  or  draw  a  series  of  wax  models  to 
show  the  development  of  the  ear  or  another  series  to  show  the 
development  of  the  eye.  If  this  is  done  consult  Figs.  122,  123,  132, 
233,  and  234  in  Atwood's  Biology. 


I  III      FROG 


67 


26.  THE  FROG 

References 

Civic  and  Economic  Biology,  Atw 1,   Figs.   22,  <>i,  g  a,,| 

Study  39. 
General  Zoology,  Linville  and  Kelley,  (Jinn  &  Co. 
New  Essentials  of  Biology,  Hunter,  pp.  272-2-    . 
Biology  for  Beginners,  Moon,  Chap.  XXYIII. 
Comparative  Vertebrate  Dissection,  At  wood,  P.  Blakiston's  Son 
Anatomy  of  the  Frog,  Ecker,  Oxford. 
Laboratory  Directions  in  Zoology,  Guyer,  U.  of  Wis.    Pr< 

200.  The  living  frog  should  be  examined  first.  I'luy  may  be  kept 
in  the  laboratory  indefinitely  by  feeding  them  twice  a  wick.  The 
first  exercise  may  be  a  demonstration  of  how  to  feed  a  frog.  I'l. 
them  in  a  dish  with  glass  sides  so  the  class  may  see  what  .  on. 
They  should  be  left  here  long  enough  to  become  quiet,  and  then  if 
pieces  of  meat  are  dangled  before  their  noses  on  a  wire,  they  will 
take  the  meat  readily.  Put  the  meat  on  the  wire  -0  that  it  may  be 
pulled  off  easily.  Will  a  frog  eat  meat  that  is  not  moving?  Will 
they  take  food  which  is  not  good  for  them?  ho  they  -wallow  all 
kinds  of  food?  Are  their  abilities  to  taste  well  developed?  Antl  • 
especially  attracted  by  certain  colors?  What  do  they  do  when  they 
secure  apiece  of  food  that  is  a  little  too  large  to  handle  easilj 

Put  one  frog  in  the  dark  and  one  in   the  light.      How  are  their 
shades    of    color    effected?     Note    the    spots    and    marking       \ 
they    protective?     Learn    to    know    the    kinds    of   frogs   by    their 
markings.     Note  that  the  skin  is  moist.      It  is  used  a-  a  respiratory 
organ. 

Locomotion.— How  does  the  frog  walk,  jump,  and  swim? 
pare  the  legs.     How  is  each  pair  used?     Compare  their  joints  with 
those   of   man's.     Locate    the    elbows,    wrist>.    knee-,    and    ankK 
Note  that  the  frog  has  no  tail. 

The  head  of  the  frog  is  po  1  of  a  very  large  mouth,  1 

nostrils,  and   ears.     Find    these  structures.     Can    '!><•   fr<  ik: 

Can  it  move  its  eves?  Compare  tin-  upper  and  lower  lid-  The 
nictitating  membrane  is  a  third  eyelid  which  is  transparent 
Observe  it. 


08 


PROJECTS    AND   EXPERIMENTS    IN  BIOLOGY 


internal  nares 
teeth 


Breathing  is  accomplished  by  filling  the  throat  with  air  and  then 
swallowing  it  into  the  lungs.  Observe  a  frog  as  it  breathes.  How  is 
the  air  expelled?  Can  it  breathe  with  its  mouth  open?  An  alliga- 
tor breathes  much  the  same  as  a  frog,  but  can  do  so  with  its 
mouth  open.  Can  you  explain?  Hold  the  frog  between  the 
finger  and  thumb  by  placing  them  under  its  arm-pits.  The 
frog  usually  croaks.  Can  it  croak  with  its  mouth  closed?  Of 
what  value  is  the  frog's  ability  to  croak  in  nature?  Can  it  croak 
underwater? 

Circulation  of  blood  may  be  shown  by  placing  a  frog's  foot  under 
the  microscope.  Various  ways  of  doing  this  have  been  devised. 
If  you  make  this  exhibit,  do  not  injure  the  frog. 

The  dead  frog  may  be  placed  in  a  pan  of  water  and  cut  open  on 
the  ventral  side  to  remove  some  of  the  formalin  in  which  it  has  been 
preserved,  or  if  it  is  fresh  we  may  study  the  inside  of  the  mouth. 

Consult  the  figure  and  locate 
the  parts  which  are  named. 
The  Eustachian  tube  may  be 
traced  to  the  ear  chamber  by 
inserting  a  probe.  The  lungs 
of  a  fresh  specimen  may  be 
inflated  by  inserting  a  blow- 
pipe in  the  trachea. 

The  skin  is  loose  and  may 
be  removed  easily.  Note  the 
blood  vessels  which  enter  the 
skin  near  the  fore  legs.  What  is 
their  use? 

The  body-cavity  may  be 
explored  after  a  cut  is  made 
along  its  mid-line  from  the  throat  to  the  hip  girdle.  Find  the  heart. 
If  the  specimen  is  freshly  killed  it  will  be  beating.  The  liver  is  the 
large  dark  red  organ  in  the  middle  of  the  cavity.  On  the  frog's  left 
and  under  the  liver  is  the  stomach.  Trace  the  intestine  from  the 
stomach  to  the  pelvic  region.  Note  its  coils.  Near  its  posterior 
end  it  is  enlarged  to  form  a  rectum.  At  its  terminus  is  a  large  sac 
which  is  the  urinary  bladder. 


esophagus 

Eustachian 
tube 


tongue 


Fig.  39. — The  open  mouth  of  the  frog 
to  show  the  structures  within.  {Drawn 
for  this  work  by  J.  Thranow.) 


Tin:   frog 


60 


The  egg  masses  may  have  interfered  with  the  observation  of  the 

intestine  if  the  specimen  was  a  female.      The  eLrL.r~  are  held  in  a  la' 


bra] 


Fig.  40. — The  arU'rirs  of  the  fr- 

sac  of  the  ovary  until  spring  when  they  are  laid.     How  large  are 
they?     What  is  their  color?     Remove  the  eggs  and  find  the  la r 

internal    jugular  ^ 


femoral 


sciatic 


F j  1 .   -The  veins  of  the 


coiled,   white   tubes   which    are   the  oviducts.      Their  wall-  contain 
stored  nutriment  which  is  added  to  th(  a-  tiny  are  laid.      I  ach 


7° 


PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 


egg  is  passed  from  the  ovary  into  the  cavity  of  the  body,  from  where 
ii  enters  the  open  end  of  the  oviduct  to  be  passed  to  the  cloaca. 
This  is  the  place  where  the  intestine  and  the  oviducts  meet.  The 
kidneys  may  be  seen  by  pushing  the  oviducts  to  one  side.  They  are 
red -brown  bodies.  Each  is  drained  by  a  duct  to  the  cloaca.  On  the 
ventral  surface  of  each  kidney  is  a  yellow  colored,  irregular  fat 
body  and  an  orange  colored  strip  of  tissue  called  the  adrenal  body. 
Find  these  bodies.     What  is  known  about  their  functions? 

The  lungs  are  simple  sacs  with  pitted  walls  in  the  chest  cavity. 
They  are  nearer  the  back  than  the  liver  which  covers  them. 


iliohypogastric  nerve 

—  —  crural    nerve 

-—  —  6Ciatic    nervr 


5t7        \ 

—  —  olfactory  capsule 
. palatine 

,5      - 

Jip^'jsN 

^"~  """ 

-  ophthalmic 

\  !k 

ev^'.'.'^v 

—  eye 

2jw5 

ni'ti'.-;* 

%\  U\- 

maxillary 

WW1 

^v  _^~0^^ 

* maxillo-mandibular 

\V  —  tympanic  membrane 
\ry  —  Gasserian  ganglion 
JL-V  —  hyomandibular 

k^ — ^jy 

7     •" 
^  1 

—  +  -glossopharyngeal 

v< — ^\A 

\  11     v 

jugal  ganglion 
-  —  — sympathetic 

"V  -  vagus 
ganglion 

43- 

—The 
nerves 

brain    and    cranial 
of  the  frog. 

Fig.  42. — The  spinal  nerves  and  Fig. 

sympathetic  nervous  system  of 
the  frog  showing  the  brachial  and 
pelvic  plexuses. 

The  blood  vessels  may  be  found  and  named  by  use  of  the  figures. 
Remember  that  the  blood  of  the  frog  passes  through  the  heart  twice 
in  making  a  complete  circuit  of  the  body.  (See  Figs.  98  and  99  in 
Atwood's  Biology.)  If  the  specimens  are  injected,  or  are  fresh, 
this  will  not  be  difficult.  But  it  is  not  possible  in  high  school 
classes  if  the  specimens  have  been  preserved  without  injection. 


THE    PROG  71 


Mesenteries  arc  thin  sheets  of  tissue  which  hold  the  organs  of  the 
body-cavity  in  place  Find  them  and  name  them  after  the  organ 
which  is  suspended  in  each  case. 

The  spinal  nerves  and  the  sympathetic  nervous  system  arc  shown 
in  the  figure.  Look  in  the  cavity  of  the  body,  along  the  inner  wall 
of  the  back,  and  find  the  white  cords  which  are  the  nerves.  Com- 
pare them  with  the  figure.  Can  you  find  them  all?  Those  which 
are  associated  at  the  level  of  the  arm  form  the  brachial  plexus, 
and  those  which  unite  to  send  branches  into  the  leg  form  the 
the  sacral  plexus.  Each  nerve  trunk  Leaves  the  spinal  cord  by  two 
branches  which  unite  to  form  a  spinal  nerve.  See  At  wood's 
Biology,  Fig.  138. 

The  brain  and  cranial  nerves  are  shown  in  the  figure-.  With  a 
sharp  pointed  scissors  the  skull  of  the  frog  may  be  cut  open  from 
above  by  inserting  a  point  in  the  back  of  the  skull  where  the  spinal 
cord  leaves  and  cutting  bit   by  bit  until   the  roof  of  the  skull  i> 


occipital 
r-  prooiic 


*¥—*■  baaiocclpit*!' 
—  ■quaxMfcl 


Fig.  44. — Side  view  of  the  skull  of  the  bullfrog. 

removed.     The  brain  should  be  seen  and  its  parts  identified  by  refer- 
ring to  Fig.  136  in  Atwood's  Biology.      It   may  not   be  possible  for 
students  of  high  school  grade   to  identify  all  of  the  cranial  ner\ 
which  are  shown  in  the  figure,  but  they  should  be  found  where  they 
arise  near  the  brain  and  traced  outward  as  far  as  possible. 

The  muscle  system  may  be  studied  by  referring  to  the  figures  in 
Comparative  Vertebrate  Dissection,  Atwood,  P.  Blakis ton's  Son  & 
Co.;  General  Zoology  Laboratory  Directions,  Sigerfoos,  Minneapolis, 
Minn.;  Anatomy  of  the  Frog,  Ecker,  Oxford. 

The  skeleton  is  divided  into  the  axial  and  the  appendicular 
parts.  The  axial  consists  of  the  skull  and  vertebral  column.  A 
view  of  the  skull  is  shown  here.  If  skeletons  are  available,  the 
bones  of  the  skull  mav  be  identified.     The  bones  of  the  vertebral 


7  2  PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 

column  are  the  vertebrae.  Each  consists  of  a  centrum  which  is  the 
main  part  of  the  bone  and  a  neural  arch  which  surrounds  the  nerve 
i  ..id.  At  the  sides  are  the  transverse  processes  which  terminate  in 
short  ribs.  It  may  almost  be  said  that  frogs  have  no  ribs.  The 
last  bone  in  the  vertebral  column  is  the  urostyle.  Account  for  its 
peculiar  shape. 

The  appendicular  skeleton  consists  of  the  limbs  and  their  support- 
ing bones.  The  shoulder  girdle  is  a  curved  plate  of  bones  and 
cartilage  which  supports  the  front  legs.  It  is  not  closely  attached 
to  the  axial  skeleton.  The  humerus  is  the  first  bone  of  the  front 
leg.  The  radius  and  ulna  are  united  to  form  the  bone  of  the  fore- 
arm. How  many  wrist,  hand,  and  finger  bones  are  there?  The 
pelvic  girdle  supports  the  hind  legs.  Is  it  attached  to  the  vertebral 
column?  The  first  bone  in  the  leg  is  the  femur.  The  tibia  and 
fibula  are  united  in  the  shank  of  the  leg.  The  ankle  is  long  and 
contains  two  long  tarsal  bones.     How  many  toes  are  there? 

Draw  such  features  of  the  anatomy  of  the  frog  as  the  instructor 
may  direct.  All  students  may  not  be  asked  to  make  the  same 
drawings. 

27.  STUDIES  ON  THE  ECONOMIC  IMPORTANCE  OF  DOMES- 
TICATED ANIMALS  AND  PLANTS 

For  a  reference  see  Unit  V,  Atwood's  Biology. 

The  author  has  not  been  accustomed  to  do  any  laboratory  work 
with  this  section  of  the  work.  It  has  been  interesting  to  work  up 
topics  and  reports,  and  devote  a  few  minutes  each  day  to  the  giving 
of  them  to  the  class;  but  their  nature  must  depend  upon  the  refer- 
ences which  are  available,  their  number,  and  upon  the  time  which  is 
given  to  this  unit  of  the  book. 

201.  Library  Committee  Work. — Prepare  lists  of  reports  on  the 
subject  matter  of  the  first  half  of  Unit  V  of  Atwood's  Biology  which, 
in  your  judgment,  can  be  made  up  from  the  reference  material  avai- 
lable in  your  library.  Submit  them  to  the  instructor  for  approval 
and  let  the  members  of  the  class  select  such  as  they  wish  to  work 
on.     This  should  be  done  before  this  study  is  taken  up  in  class. 


VARIATION   AND    HEREDITY  73 

202.  Exhibits.- Hie  museum  committee  should  prepare  exhibits 
of  such  grains,  fruits,  vegetables,  etc.  as  are  available  and  as  will  be 
instructive  to  the  class. 

203.  Government  bulletins  of  the  department  of  agriculture  may 
be  had  for  the  asking.  Write  to  the  Editor  in  Chief  of  the  Depart- 
ment of  Publications,  Department  of  Agriculture,  Washington, 
D.  C,  and  get  your  name  on  the  monthly  mailing  list  of  announce- 
ments of  new  bulletins.  Much  valuable  information  bearing  on 
these  studies  may  be  had  from  these  bulletins.  They  should  be 
placed  in  charge  of  the  library  committee.  It  is  possible  to  get  a 
catalogue  of  bulletins  which  have  been  published  in  the  past  and 
are  still  in  print. 

204.  Class  Projects. — Make  a  tabulation  of  the  domesticated 
plants  and  list  their  wild  ancestor,  or  ancestors,  and  the  country 
from  which  they  came. 

Repeat  the  above  for  the  domestic  animals.  If  time  is  short,  a 
select  list  may  be  sufficient  in  both  cases. 


28.  VARIATION  AND  HEREDITY  AND  THEIR  APPLICATION 
TO  PLANT  AND  ANIMAL  BREEDING 

References 

Civic  and  Economic  Biology,  Atwood,  Studies  46  and  47. 
Heredity  and  Evolution  in  Plants,  Gager,  Chaps.  IV  and  V. 
Being  Well  Born,  Guyer,  Bobbs-Merrill  Co. 
Genetics,  Walter,  Macmillan  Co. 
Elementary  Biology,  Gruenberg,  Part  V. 

205.  Variation  Study. — Refer  to  Fig.  256,  Atwood's  Biology  and 
make  a  list  of  all  of  the  ways  in  which  the  two  ears  of  corn  differ,  the 
one  from  the  other.  When  the  lists  are  complete  they  should  be 
compared  in  class.  Note  length,  diameter,  kernels  in  the  row,  size 
of  kernels,  rows  of  kernels,  butts,  tips,  shape  of  ear,  curved  or  straight, 
and  any  other  variations  which  you  may  note.  What  might  haw- 
been  the  cause  of  some  of  these  variations? 

206.  Reports  may  be  prepared  on  cases  of  discontinuous  variations 
which  are  known  in  the  literature  of  science. 


74 


PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 


207.  Tabulate  all  of  the  animals  which  you  know  to  produce  albino 
offspring  on  occasions.  List  the  dates  and  places  of  occurrence. 
Make  another  tabic  for  the  occurrence  of  black  animals. 

208.  Exhibits. — Try  to  secure  for  exhibition  purposes  in  the 
laboratory  specimens  of  Andalusian  fowls,  white  rats  and  mice, 
guinea  pigs,  and  hybrid  plants. 

209.  Chromosome  Chart. — See  p.  314  in  Atwood's  Biology  and 
by  referring  to  the  chromosome  inheritance  chart  write  an  explana- 
tion of  how  the  laws  of  Mendel  and  the  theory  that  the  chromosome  is 
the  carrier  of  the  determiners  of  heredity  are  in  agreement. 


PARENTS 


SECOND        GENERATION 

Fig.  45. — Chart  to  show  how  the  chromosome  theory  of  inheritance  is  in 
accord  with  Mendel's  laws.  The  chromosomes  which  carry  the  determiners  of 
black  color  are  black  in  the  figure,  and  those  which  carry  white  are  white. 

210.  Exhibit. — If  possible  specimens  of  various  breeds  of  corn, 
wheat,  apples,  squashes,  etc.  should  be  shown  to  the  class. 

211.  Quetelet's  Law. — This  is  the  law  of  chance.  It  may  be 
illustrated  by  taking  ten  pennies  and  throwing  them  up  a  thousand 
times  and  recording  the  number  of  heads  and  tails  in  a  table  with 
eleven  columns;  or  five  pennies  may  be  chosen  and  recorded  in  a 


PLANT    AND    ANIMAL   BREEDING  75 

table  with  six  columns.  In  this  case  it  may  be  sufficient  to  throw 
them  up  about  500  times.  Take  your  results  to  an  adding  machine 
and  compare.  Plot  a  curve  of  the  results.  Continuous  variations 
follow  this  curve  in  their  occurrence. 

This  law  may  also  be  shown  with  the  apparatus  which  is  illustrated 
in  Fig.  394,  Fund  a  men  tals  0}  Botany,  Gager. 

Secure  ioo  earthworms  and  count  the  rings  in  their  bodies.  Colic.  I 
the  data  in  a  chart  and  plot  the  curve.     Is  it  a  Quetelet  curve? 

Secure  ioo  ears  of  corn  of  the  same  variety  and  count  the  rows 
of  kernels,  or  measure  the  lengths,  or  diameters.  Suggest  other 
problems  or  projects  which  might  be  worked  out.  Do  you  fully 
realize  the  universality  of  this  law? 

212.  Board  Work. — Write  down  the  various  types  of  discontinuous 
variations  in  a  table  form.  Recall  or  give  examples  of  the  various 
cases  of  mutations  of  which  you  know  or  have  read.  Assign  each 
to  its  proper  place  in  the  table.  When  this  is  done,  the  table  may 
be  copied  in  the  notebook. 

213.  Trap  Nests. — A  report  may  be  given  to  the  class  on  the 
subject  of  increasing  the  production  of  eggs  by  trap-nesting  the 
laying  hens. 

214.  The  Babcock  Milk  Test. — A  demonstration  of  this  test  may 
be  given  here  if  it  was  not  done  in  connection  with  the  food  tests. 
Of  what  value  is  milk  testing  in  improving  cows? 

215.  Corn  testing  and  judging  demonstrations  may  be  carried 
out  before  the  class.     See  Government  Bulletins  for  directions. 

216.  A  report  may  be  given  to  the  class  on  the  life  and  work  of 
Luther  Burbank. 

217.  Prepare  a  list  of  the  wild  animals  in  your  community  which 
are  hunted  and  trapped  for  their  furs.  Which  ones  will  live  and 
breed  in  captivity?  What  are  the  game  laws  which  protect  them? 
If  our  wild  life  continues  to  decrease  as  it  now  is,  we  will  soon  pro- 
duce nearly  all  of  our  furs  from  domesticated,  furred  animals.  If 
there  is  a  fox,  skunk,  or  muskrat  farm  in  the  vicinity  it  may  be  possi- 
ble to  make  a  study  of  it. 

218.  Animal  Improvement  Study. — Refer  to  Figs.  250  and  251 
in  Atwood's  Biology  and  make  a  list  of  the  changes  which  have  taken 
place  in  the  production  of  the  zebu  cattle  from  the  wild  banteng. 


76 


PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 


29.  EUGENICS  AND  EUTHENICS 

References 

Civic  and  Economic  Biology,  At  wood,  Studies  46,  47,  51,  and  52. 

Civic  Biology,  Hunter,  Chaps.  XVII  and  XXIV. 

Civic  Biology,  Hodge  and  Dawson,  Chap.  XXX. 

Genetics,  Walter,  Macmillan  Co. 

Being  Well  Born,  Guyer,  Bobbs-Merrill  Co. 

Tin  Next  Generation,  Jewett,  Ginn  &  Co. 

219.  Reports  on  state  laws  on  eugenics,  marriage  laws,  population 
of  the  asylums  of  the  state,  tree  ordinances,  nature  of  adenoids, 
duties  of  the  health  department,  results  of  school  inspection  for 
teeth,  eyes,  and  other  ailments  needing  attention,  suggestions 
for  improvement  of  the  ventilation,  lighting,  and  heating  systems 
of  schools,  relative  humidity,  child  labor  laws  in  your  state,  value  of 
pure  water  and  milk,  etc.,  are  of  great  value.  We  can  not  hope  to 
make   much   more   progress   in  civic  betterment  along  biological 


A 


oim 


A 


b\m 


□    MALE 
O    FEMALE 


.... 


A  -  ALCOHOLIC 
!•  FEEBLEMINDED 


Fig.  46. — Three  marriages  to  show  how  feeblemindedness  is  inherited.  De- 
scribe in  writing  what  the  results  are  as  shown  in  the  diagram.  {General  Science, 
Brownell.) 

lines  until  the  general  public  has  more  information  of  these  matters 
than  it  now  has,  and  until  it  has  a  greater  desire  to  profit  by  such 
knowledge. 

220.  Table  of  Inherited  Defects. — Make  a  tabulation  on  the  board 
of  the  defects  which  people  have  which  are  inherited.  If  there  is 
doubt  about  it,  write  a  question  mark  to  so  indicate.  Copy  the 
table  in  the  notebook  and  file  a  copy  with  the  archives  committee. 


EUGENICS    AND    EUTHENICS  77 

221.  Research. — Consult  the  table  on  p.  306,  Atwood's  Biology 
and  understand  how  inherited  defects  are  charted.  If  you  know  of 
any  people  or  animals  having  inherited  defects,  try  to  get  some 
data  concerning  them  and  their  relatives.  When  it  is  collected  it 
should  be  charted  as  in  the  figure.  In  making  such  surveys  be  very 
careful  to  avoid  giving  offense  to  people  who  may  be  sensitive. 

222.  Family  Survey. — Make  an  inheritance  chart  of  the  occur- 
rence of  Mendelian  characters  in  your  family.  Make  the  chart  as 
inclusive  of  as  many  individuals  as  possible.  Eye-color,  hair-color, 
curly  or  straight  hair,  fatness,  and  musical  ability  are  such  character- 
as  may  be  easily  charted. 

223.  Questions. — Is  feeble-mindedness  dominant  or  recessive? 
Can  normal  children  be  born  from  feeble-minded  parents?  If 
feeble-mindedness  is  due  to  disease  or  injury,  will  it  be  inherited  ?  Is 
insanity  inherited?  May  it  be  caused  by  injury?  If  there  are  no 
millions  of  people  in  the  United  States  and  20  per  cent  of  them 
have  some  inherited  defect,  how  many  such  people  have  we?  Make 
a  list  of  human  defects  and  classify  them  as  to  whether  they  are  bad 
enough  to  be  eliminated  by  segregating  those  who  have,  them  or 
should  no  restrictions  be  placed  upon  them.  Baldheadedness 
and  fatness  are  of  the  kind  which  should  not  be  restricted.  Should 
one  consider  the  relatives  of  the  person  whom  one  wishes  to  marry? 
Is  a  person  to  be  blamed  for  being  a  defective?  Therefore,  should 
we  not  be  charitable  to  them? 

224.  Shrub  Study. — Make  a  trip  through  the  city  to  study  the 
shrubs  which  are  used  for  improving  the  appearance  of  yards  and 
boulevards.  Make  a  list  of  them,  and  star  the  best  ones.  See  the 
catalogues  of  nurserymen  as  references. 

225.  Landscape  Garden  Plans. — Have  the  local  landscape  gardner 
give  the  class  a  talk  on  the  science  and  art  of  his  profession.  Make  a 
diagram  of  your  home  and  the  shrubs  and  trees  which  surround 
it.  Is  there  room  for  improvement  ?  Will  there  be  some  flower  beds 
next  summer?  Have  some  of  the  plans  put  on  the  board  and  dis- 
cussed as  to  possible  improvement  by  the  class. 

226.  Notebook  Work. — Answer  (he  questions  which  are  asked  in 
the  studies  on  eugenics  and  euthenics  in  At  wood's  Biology,  Studies 
51  and  52.     Read  the  following  references  and  write  an  outline  or 


78  PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 

summary  of  each:  The  Kallikak  Family  by  Goddard,  the  Zeros  by 
Poellman,  Noteworthy  Families  by  Galton,  The  Heredity  of  Richard 
Roc  by  Jordan,  and  the  Descendants  of  Jonathan  Edwards  by  Winship. 


30.  THE  DOCTRINE  OF  EVOLUTION 

References 

Civic  and  Economic  Biology,  Atwood,  Unit  VI. 

Heredity  and  Evolution  in  Plants,  Gager,  P.  Blakiston's  Son  &  Co. 

The  Theory  of  Evolution,  Scott,  Macmillan  &  Co. 

227.  Field  Trips. — Go  to  a  stone  quarry,  gravel  bed,  the  shore 
of  the  ocean,  or  one  of  the  Great  Lakes  and  study  the  fossils  which 
are  to  be  found  there. 

Go  to  a  museum  and  observe  the  fossils  which  are  there. 
Various  members  of  the  class  may  be  able  to  bring  fossils  to  the 
class  for  observation. 

228.  Reports  may  be  given  on  the  ancestry  of  the  horse,  elephant, 
camel,  birds,  mammals,  ancient  and  primitive  man,  plants  of  the 
carboniferous  period. 

229.  Demonstration. — Compare  the  skeletons  of  various  animals 
to  demonstrate  that  all  vertebrates  are  built  on  the  same  plan. 
What  other  systems  may  be  used  to  show  this? 

230.  Table  of  Vestiges. — Make  a  tabulation  of  the  various  vesti- 
gial structures  of  animals  which  you  know  and  list  their  probable 
use  in  ancestors  which  had  them  in  a  perfect  form. 

231.  Reports  on  the  lives  of  some  of  the  great  men  of  biology 
may  be  prepared  and  given  from  time  to  time  as  they  are  ready. 

232.  Overproduction  Computations. — If  we  start  with  a  pair  of 
flies  in  the  spring,  and  the  female  lays  200  eggs,  and  the  young 
develop  and  lay  eggs  again  in  30  days,  and  the  summer  lasts  five 
months,  how  many  flies  will  there  be  at  the  end  of  summer? 

If  a  certain  weed  produces  3,000  seeds  in  a  season,  and  all  grow 
each  year,  how  many  weeds  will  there  be  in  ten  years?  If  each 
weed  weighs  ten  pounds,  how  much  will  all  of  them  weigh? 

If  a  pair  of  eagles  produce  two  young  each  year  and  live  to  be 
100  years   old,  and  if  breeding  takes  place  the  second  year,  how 


BACTERIA,  YEASTS,  AND  MOLDS  79 

many  eagles  will  there  be  at  the  end  of  ioo  years?     If  this  problem  is 
too  long,  it  may  be  estimated. 

233.  Struggle  for  Existence  Experiment.—  Plant  several  kinds  of 
seeds  in  a  box  or  tray.  Plant  a  great  many  seeds.  Give  the  culture 
the  best  of  care.  What  seedlings  survive?  Did  they  struggle?  Is 
it  not  obvious  that  they  can  not  all  live? 

234.  Reports.— List  the  different  kinds  of  the  following  animals 
and  plants  which  man  has  produced  by  natural  selection.  Do  not 
be  discouraged  if  you  can  not  give  a  complete  list.  Get  as  many 
pictures  to  show  as  you  can. 

Varieties  of  dogs. 
Varieties  of  chickens. 
Varieties  of  doves. 
Varieties  of  apples. 

Reports  of  famous  biological  experiments  and  discoveries  will  be 
interesting  and  valuable. 

31.  BACTERIA,  YEASTS,  AND  MOLDS 

References 

Civic  and  Economic  Biology,  Atwood,  Studies  56  and  57. 
Practical  Botany,  Bergen  and  Caldwell,  Chap.  XI. 

235.  Bread  mold  may  be  grown  on  bread  by  moistening  it  and 
placing  it  in  a  warm,  damp  place  for  a  day  or  two  when  it  will 
be  covered  with  the  hyphae  of  the  fungus;  and  in  a  day  or  two  more, 
the  black  spore  cases  will  appear. 

Growth  tests  for  bread  mold  may  be  made  as  follows:  Secure 
eight  wide  mouthed  bottles  or  tumblers.  Place  a  piece  of  bread 
which  is  wet  in  each  vessel  and  treat  each  as  follows: 

1.  Do  nothing.     This  is  the  control. 

2.  Remove  the  bread  from  the  glass.  Clean  the  glass  and  dry  it. 
Dry  the  bread  completely  and  replace  it  in  the  glass. 

3.  Cover  the  piece  of  bread  with  dry  salt. 

4.  Cover  the  bread  with  vinegar  or  some  other  acid  as  boracic. 

5.  Place  enough  sugar  on  the  bread  to  cover  it.  Corn  sirup  may 
be  substituted  for  the  sugar. 


8o  PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 

6.  Place  the  glass  containing  the  moistened  bread  in  boiling  water 
in  a  double  cooker  or  a  sterilizer.     Keep  covered  after  removing. 

7.  Place  this  one  in  a  refrigerator. 

8.  Place  on  the  bread  a  dilute  solution  of  formalin. 

Place  all  but  No.  7  in  a  warm  place  and  keep  each  vessel  covered 
to  prevent  evaporation  and  more  infection.  In  order  to  make  sure 
that  each  was  infected  with  mold,  it  might  be  well  to  inoculate  each 
piece  at  the  start.  The  cultures  should  be  examined  at  the  end  of 
four  days  and  the  results  written  in  the  notebook.  Be  sure  to  explain 
why  mold  failed  to  develop  in  the  sterile  cultures. 

236.  Microscopic  Work. — Bacteria  may  be  spread  on  microscope 
slides,  dried,  stained,  and  viewed  with  the  high  power. 

Yeasts  are  easily  seen.  They  are  very  large  cells.  Place  a  drop 
of  the  culture  in  which  they  are  growing  on  a  microscope  slide  and 
view  under  the  low  and  high  power.  What  is  the  shape  of  the  cells? 
Note  how  they  grow  by  budding.  Can  you  find  a  nucleus?  A 
drop  of  iodine  on  the  slide  will  enable  you  to  avoid  starch  grains. 
How? 

Draw  some  yeast  cells  to  show  their  shape,  nuclei,  and  their  method 
of  growth  and  reproduction. 

237.  Project. — Refer  to  Atwood's  Biology,  Fig.  299  and  make 
some  wax  models  of  various  kinds  of  bacteria  as  suggested. 

238.  Molds. — From  some  of  the  cultures  of  bread  mold  which 
you  have  grown,  you  may  secure  material  which  can  be  viewed  under 
the  microscope.  Find  the  hyphae,  stolons,  rhizoids,  sporangio- 
phores,  and  spore  cases  (sporangia).  Make  a  drawing  showing 
these  structures  and  label  carefully. 

239.  Culture  Medium.. — The  best  medium  for  the  cultivation  of 
bacteria  is  the  beef  extract-agar-bouillon.  To  make  it,  dissolve 
ten  grams  of  each  of  the  following  materials  in  200  cc.  of  water: 
Leibig's  beef  extract,  salt  (NaCl),  and  peptone.  In  800  cc.  of  boiling 
water  dissolve  ten  grams  of  agar-agar  (or  100  grams  of  gelatin). 
The  agar  must  be  given  considerable  time  in  which  to  dissolve,  and 
must  be  kept  at  a  boiling  temperature  in  a  double  cooker.  Pour 
the  first  solution  into  the  second  and  filter  while  hot  through  cotton. 
It  should  be  clear.  If  it  is  not,  it  should  be  heated  again  and 
refiltered, 


BACTERIA,    YKASTS,    AND    SCOLDS 


81 


Pour  the  hot  culture  medium  into  sterilized  test  tubes  and  Petri 
dishes.  The  dishes  should  be  covered  immediately  and  the  test 
tubes  should  be  plugged  with  sterilized  cotton.  Set  these  away 
to  be  inoculated  in  the  following  experiments. 

Note. — This  solution  should  be  made  by  the  instructor  or  by  a  responsible 
committee.  If  the  medium  is  to  be  used  for  bacteria,  it  should  be  made  slightly 
alkaline  by  the  addition  of  sodium  carbonate;  but  if  it  is  to  be  used  for  molds,  it 
should  be  slightly  acid.  Determine  the  acidity  or  alkalinity  after  it  is  filtered  by 
using  litmus  paper. 


Fig.  47. — Bread  mold  (Rhizopus  nigricans)  to  show  its  habit  of  growth. 
A,  Older  plant  with  ripe  spores;  B,  younger  plant  with  unripe  spores;  myc, 
mycelium;  sph,  sporangiophore;  sp,  sporangium;  si,  stolon.  {Fundamentals  of 
Botany,  Gagcr.) 


240.  Where  may  bacteria  te  found? — Expose  the  Petri  dishes 
in  some  of  the  following  ways.  To  the  dust  of  the  room  while  it  is 
being  swept.  To  dirt  from  under  the  finger  nails.  To  a  comb  after 
passing  it  through  the  hair.  Wash  the  hands  in  a  small  amount 
of  water  and  place  a  drop  of  it  on  the  culture.  Scrape  the  teeth 
with  a  dry,  sterile  tooth  brush  and  inoculate  a  culture  with  the 
scrapings.  Get  some  dust  from  the  road,  from  a  window  ledge, 
from  a  basement,  and  other  places  and  inoculate  cultures. 

Keep  the  cultures  in  a  warm  place  and  do  not  let  them  dry  out. 
Watch  them  and  report  the  growths  as  they  take  place.  Do  not 
remove    the   covers   when    examining    Petri    dishes.     Compare    the 


S2 


PROJECTS   AND   EXPERIMENTS   IN  BIOLOGY 


growths  in  the  different  dishes.  How  can  you  tell  molds  from 
bacteria?  Are  there  any  differences  in  the  kinds  of  molds  and  the 
kinds  of  bacteria?  Do  you  fully  understand  how  these  fungi  got 
into  the  Petri  dishes?  Are  bacteria  everywhere  in  the  house  and 
out  of  doors?     Probably  none  of  the  bacteria  which  you  have  grown 


Fig.  48. — A  plate  culture  of  colonies  of  bacteria  grown  from  a  bit  of  dust  from  a 

cow  stable.      (Microbiology,  Marshall.) 

are  dangerous  to  man  as  producers  of  contagious  diseases,  but  if 
you  had  secured  your  inoculating  material  from  a  sewer,  spittoon, 
or  scab  it  would  be  dangerous. 

241.  Pure  cultures  of  bacteria  may  be  made  by  thrusting  a 
sterilized  needle  or  platinum  wire  in  a  spot  of  bacteria  in  a  Petri  dish 
and  then  thrusting  it  in  the  culture  medium  which  you  have  saved  in 
a  test  tube.     Be  very  careful  to  avoid  letting  any  foreign  bacteria 


BACTERIA,    YEASTS,    AND    MOLDS 


83 


get  into  the  tube  when  the  inoculation  is  made.  After  a  few  days 
the  tubes  may  be  examined.  If  you  were  careful,  there  will  be  but 
one  kind  of  bacteria  in  a  test  tube.  Do  you  fully  appreciate  how 
careful  one  must  be  to  avoid  bacteria  which  cause  decay  or  disea 

242.  Problem. — If  the  bacillus  tuberculosis  divides  every  half 
hour  when  it  is  growing  rapidly,  and  you  should  become  infected 
with  it,  how  many  germs  would  there  be  in  your  body  at  the  end  of 
ten  hours?  Twenty  hours?  One  month!  What  prevents  them 
from  multiplying  as  fast  as  they  might? 

243.  Project. — Secure  several  kinds  of  food  and  vegetables. 
Cut  the  vegetables  in  slices  and  mix  the  foods  with  water.  Keep 
them  warm  and  moist.  The  class  should 
see  them  each  day.  Which  foods  are 
attacked  the  more  readily?  Are  any 
resistant  to  decay? 

244.  Committee  Field  Trip.  —  Some 
members  of  the  class  may  go  into  the 
woods  and  find  shelf  fungi  growing  on 
trees.  Note  whether  the  trees  are  alive 
or  dead.  On  what  kinds  of  trees  are 
they  found?  Bring  some  of  the  speci- 
mens to  the  class  and  put  them  in  the 
museum.  Give  a  report  of  your  trip  to 
the  class  and  file  a  record  of  it  with  the 
archives  committee. 

245.  Museum  Exhibit. — The  museum 
committee  will  prepare  an  exhibit  of  the 
various  kinds  of  fungi  which  may  be  in 

+U~     ™  tl  u-    u  i_  e    1  FlG-     4  9-  — FcrnuMUati.-n 

the  cases.  I  hose  which  are  harmful  tube  for  the  study  of  gas  for- 
to  our  fruit  trees  are  of  great  economic    mation  by  yeasts  and  bacteria. 

_^  ...  .  '  ,  .  ,       (From  Pit  field  ajter  Williams.) 

importance.     Edible    mushrooms  which 

have  been  preserved  in  formalin  may  be  seen  now  and  a  field 
trip  planned  for  the  spring,  but  more  of  them  arc  to  be  found  in  the 
fall.  If  there  is  a  mushroom  cellar  in  the  city  it  may  be  possible  to 
visit  it. 

246.  Yeast  plants  may  be  grown  in  dilute  solutions  of  sugar, 
glucose,  honey,  sirup,  or  dough.     Some  of  the  material  may  be  put 


84  PROJECTS    AND    EXPERIMENTS    IN   BIOLOGY 

in  fermentation  tubes,  and  some  of  them  placed  in  a  refrigerator 
and  some  in  a  warm  place.  Which  shows  the  most  gas  at  the  top 
of  the  tube?  Smell  of  the  cultures.  What  is  the  gas  which  is 
produced?  Some  of  it  may  be  passed  from  a  flask  through  a  tube 
into  some  fresh  limewater.  How  does  this  prove  the  gas  to  be 
carbon  dioxide? 

247.  Reports. — How  is  grain  alcohol  made  on  a  commercial  basis? 
How  is  cider  made?  How  is  vinegar  made?  Read  the  reports  to 
the  class. 

248.  Questions. — Why  does  salt  pork  keep?  Why  does  smoked 
meat  keep?  How  does  sugar  preserve?  How  does  vinegar  pre- 
serve? Why  do  tomatoes  keep  better  when  canned  than  corn  or 
pumpkin?  Can  you  make  pumpkin  keep  when  canned  in  the 
kitchen?  Will  teeth  which  are  kept  perfectly  clean  decay?  Which 
is  better,  a  broom  or  a  vacuum  cleaner? 


32.  BACTERIA  AND  CONTAGIOUS  DISEASES  OF  MAN 

References 

Civic  and  Economic  Biology,  Atvvood,  Studies  58  and  59. 
Civic  Biology.  Hodge  and  Dawson,  Chaps.  XXI-XXIII. 
Civic  Biology.  Hunter,  Chap.  XI. 
New  Essentials  of  Biology,  Hunter,  Chap.  XXX. 
Practical  Botany,  Bergen  and  Caldwell,  Ginn  &  Co. 

Do  not  experiment  with  bacteria  which  cause  disease  in  man.  It  is 
dangerous.     They  may  be  studied  from  models,  charts,  and  pictures. 

249.  Statistical  Projects. — Consult  bulletins  of  the  departments 
of  health — national,  state,  and  city — and  make  charts  showing  the 
decrease  in  deaths  from  typhoid,  yellow  fever,  tuberculosis,  and 
smallpox  in  recent  years.     To  what  has  this  been  due? 

250.  Make  charts  to  show  the  increase  in  certain  seasons  of  the 
year  of  pneumonia,  malaria,  typhoid  fever,  and  summer  complaint. 
What  causes  this  seasonal  fluctuation? 

251.  Collect  statistics  to  show  the  value  of  vaccination  for  small- 
pox, and  the  use  of  antidiptheric  serum.  Do  these  figures  prove 
that  these  practises  are  valuable? 


CiiXTAC.IOUS    DISKASI'.S    OF    MAX 


85 


Collect  statistics  to  show  the  decrease  in  deaths  of  infants  in 
recent  years?  Docs  the  milk  inspection  and  quarantine  enforcement 
help  in  this  matter? 

Collect  figures  which  show  that  cancer  is  increasing.  How  do 
you  account  for  this? 

252.  Topics  may  he  prepared  giving  the  symptoms,  incubation 
periods,  and  methods  of  treatment  for  some  of  our  common  conta- 
gious diseases. 

253.  References  for  the  above  may  be  difficult  to  find.  The 
journal  of  the  American  Medical  Asso- 
ciation is  valuable,  as  are  other  reliable 
magazines.  You  should  not  trust  all 
books  and  periodicals  for  your  infor- 
mation. There  is  much  incorrect  in- 
formation in  the  current  literature  on 
the  subject  of  disease  and  health. 

254.  Life  History  of  the  Mosquito. — 

If  it  is  now  spring,  the  eggs  and  larvae 

of  mosquitoes  may  be  found  in  stagnant 

water.     Let  each  member  of  the  class 

search    for    them.     Report    all    of    the 

places    where    they   are   found.     Place 

the  wrigglers  in  screened  aquaria  in  the 

laboratory   and   watch    them   develop. 

Specimens  may  be  taken  out  and  drawn 

in  outline.     Make  a  series  to  show  how 

they    look    at    different    ages.     Adult 

mosquitoes  may  be  dried  and  placed  on 

microscope  slides,  then  covered  with  a 

drop  of  balsam,  and  a  cover  glass  mav      ■FlG"  5°~ 

.  °.  J     pi  pirns,     t.    Tracheal    gills;    r, 

be  pressed  down  upon  it.  This  prepa-  respiratory  tube.  (Entomolo 
ration  is  not  perfect  but  it  will  be  of  /'"/v'""-) 
value  in  studying  the  parts  of  the  mosquito  under  the  microscope. 
Find  the  antennae  of  the  males  and  females  and  compare.  Note 
the  long  legs.  Can  mosquitoes  stand  on  the  surface  of  quiet  water? 
Do  you  know  any  other  creatures  which  can?  How  many  wings 
has   a  mosquito?     Why  do  they  buzz?     Onlv  the  females  do  this. 


86 


PROJECTS   AND   EXPERIMENTS   IN  BIOLOGY 


Find  the  probosis  and  distinguish  its  parts.     See  Studies  25  and  58 
in  At  wood's  Biology. 

Place  some  mosquito  larvae  in  an  aquarium  with  goldfish  and 
minnows.     (?)     Make  a  list  of  the  ways  of  fighting  mosquitoes. 


Fig.  51. 


-Comparison  of  the  pupae  of  Culex  (at  left)  and  Anopheles  (at  right)- 
enlarged.      (From  Howard.) 


Which  methods  can  be  used  in  your  community?  If  you  live  in  a 
district  where  there  is  no  malaria,  is  it  worth  while  to  fight  the 
mosquito? 

255.  Personal  Survey. — See  General  Science,  Bowden,  p.  596  and 
make  the  survey  which  is  outlined  there.     If  you  have  made  it  last 


— — „7^r-, .„.„„-„„_ .-  ,  ,    ,,,    >•»:•?••  i">»y>,l!»>/»»W>it 


Fig.  52. — Anopheles  mosquito  at  left,  culex  at  right,  to  show  their  characteristic 
attitudes  when  at  rest.      {Elements  of  Animal  Biology,  Holmes.) 


year,  repeat  it  now  and  note  any  improvement  which  may  appear. 
Be  especially  accurate  in  the  examination  of  your  skin,  eyes,  ears, 
nose,  and  mouth.  You  will  not  be  required  to  show  your  report  to 
the  members  of  your  class. 


CONTAGIOUS   DISEASES   OF   PLANTS  87 

33.  CONTAGIOUS  DISEASES  OF  PLANTS 

References 

Fund  a  menials  of  Botany,  Gager,  Chaps.  XIX  to  XXI. 

Fungus  Diseases  of  Plants,  Duggar,  Ginn  and  Co. 

M ycology  and  Plant  Pathology,  Harshberger,  P.  Blakiston's  Son  &  Co. 

Chic  and  Economic  Biology,  Atwood,  Studies  60  and  61. 

Principles  of  Botany,  Bergen  and  Davis,  Ginn  and  Co. 

Bulletins  of  the  United  States  Department  of  Agriculture,  and  of  the  Slates. 

256.  Charts. — See  Fig.  305  in  Atwood's  Biology  and  make  similar 
charts  to  show  the  life  histories  of  other  fungi  which  cause  diseases 
in  plants. 

257.  Exhibits  may  be  made  of  the  specimens  which  are  in  the 
museum.  Collect  as  much  material  showing  plant  diseases  as  you 
can.  Some  of  it  must  be  kept  in  formalin,  but  much  of  it  can  be 
dried. 

258.  Reports  may  be  prepared  and  given  on  the  more  common 
plant  diseases.  Describe  how  they  are  caused.  What  parts  of  the 
plant  are  affected.  How  they  are  carried.  How  they  pass  the 
winter.     How  they  are  treated  and  cured  or  eliminated. 

259.  Table. — Make  a  table  listing  the  common  plant  diseases, 
the  plants  which  they  injure,  and  the  method  of  preventing  or 
fighting  them.  Let  each  student  work  on  a  chart,  exhibit,  report, 
or  table. 

260.  Lilac  mildew  has  been  a  favorite  for  the  study  of  a  parasitic 
fungus  for  a  long  time.  Gather  the  leaves  of  the  lilac  and  dry  them. 
View  the  spore  cases  under  the  microscope  and  draw  them.  How 
do  the  filaments  of  the  fungus  emerge  from  the  leaf?  There  is  a 
similar  fungus  on  the  leaves  of  willow  which  is  good  material  for 
study.     Consult  a  reference  and  learn  the  life  history. 


SS  PROJECTS    AND   EXPERIMENTS   IN  BIOLOGY 

34.  WEEDS 

References 

Practical  Botany,  Bergen  and  Caldwell,  Ginn  &  Co.,  Chap.  XXV. 
Civic  and  Economic  Biology,  At  wood,  Study  62. 
Civic  Biology,  Hodge  and  Dawson,  Chap.  VII. 

The  departments  cf  agriculture  of  Minnesota,  Michigan,  Ohio,  and  Wisconsin 
issue  excellent  bulletins  on  weeds.  There  are  several  issued  by  the  U.  S. 
I  department  of  Agriculture. 

261 .  Field  Trip. — If  it  is  now  spring,  go  into  the  fields  and  find  such 
weeds  as  you  can.  Learn  their  names  and  get  as  much  of  the 
following  information  from  literature  and  by  observation  as  possible. 

How  large  does  the  weed  get?  Where  does  it  grow?  What  soil 
is  best  suited  to  it?  Can  it  grow  in  water?  Is  it  easily  frozen? 
Does  its  root  live  over  winter  ?  What  crops  does  it  damage  the  most  ? 
Has  it  any  other  methods  of  reproduction  than  by  seed?  How  are 
its  seeds  scattered?  Does  it  produce  many  seeds?  Is  it  poisonous? 
Does  it  have  a  bad  taste  or  smell?  Is  it  extensively  eaten  by  animals 
or  insects?  Is  it  easily  uprooted  or  trampled  out?  Can  it  grow 
well  in  the  shade?  Does  it  harbor  any  harmful  insects?  Does  it 
produce  burs,  berries,  or  large  seeds?  Has  it  a  blossom?  What 
effect  might  the  above  have  on  the  ability  of  the  weed  to  maintain 
itself?  It  may  be  possible  to  collect  the  above  in  the  form  of  a 
table  for  the  common  weeds  of  your  community. 

262.  Survey. — The  survey  committee  may  look  for  poison  ivy, 
barberry,  poison  sumach,  poison  hemlock,  poison  oak,  jimson  weed, 
and  fennel.  Can  some  of  these  weeds  and  shrubs  be  removed? 
Keep  a  record  of  where  they  were  found  and  the  next  class  will  follow 
up  the  work  of  their  eradication. 

263.  The  following  figures  in  Atwood's  Biology  are  pictures  of 
weeds.  Which  ones  of  them  have  you  found?  Figs.  10,  26,  28, 
29,  40,  41,  43,  47,  63,  64,  106,  107,  108,  156,  163,  174,  176,  178,  180, 
181,  182,  191,  192,  194,  195,  199,  202,  311,  312,  313,  314,  316,  317. 

264.  Weed  Seed.— Examine  a  sample  of  clover  seed  which  con- 
tains the  seeds  of  weeds.  Use  a  lens.  Compare  the  weed  seeds 
which  you  find  with  those  shown  in  Fig.  317,  Atwood's  Biology. 
How  many  kinds  have  you  found?     What  per  cent  of  the  seed  was 


PARASITIC    WORMS  89 

weed  seed?     What  is  the  law  in  your  state  in  regard  to  weed  seed  in 
seed  which  is  sold  for  planting? 

35.  PARASITIC  WORMS 

References 

General  Zoology,  Pearse,  Henry  Holt  &  Co. 

Textbook  of  /.oology,  Galloway,  P.  Blakiston's  Son  &  Co. 

Civic  and  Economic  Biology,  At  wood,  Study  63. 

Civic  Biology,  Hodge  and  Dawson,  Chap.  XXIV. 

265.  The  tapeworm  may  be  observed  in  the  laboratory  by  passing 
a  preserved  specimen  around  the  class.  Microscope  slides  on  which 
are  mounted  proglottides  to  show  their  parts  may  be  had  from  the 
dealers.  These  may  be  observed  under  the  microscope  and  com- 
pared with  Fig.  319  in  Atwood's  Biology  and  drawn.  Label  all 
features  completely.  Ward,  Rochester,  N.  Y.  makes  an  excellent 
model  of  a  proglottid  of  the  tapeworm.  It  may  be  drawn  by  the 
students.  How  do  the  eggs  get  out  of  the  ovaries  to  the  exterior? 
What  is  the  function  of  the  uterus? 

266.  Ascaris  may  be  observed  from  bottles  containing  preserved 
specimens.  Sometimes  eggs  may  be  found  in  the  females.  They 
may  be  seen  under  the  microscope. 

267.  Trichina  may  be  studied  from  microscope  slides.  They  may 
be  had  from  the  dealers.  If  the  slides  are  made  from  the  llesh  of  the 
rat  or  pig  which  contains  the  larva?,  the  student  should  consult  Fig. 
321  in  Atwood's  Biology  and  make  sketches  of  what  he  sees  under 
the  microscope. 

268.  The  hook-worm  may  be  studied  from  slides,  but  few  schools 
are  supplied  with  such  material,  and  it  is  not  easily  obtained. 

269.  Topics. — Secure  bulletins  from  the  U.  S.  Public  Health 
Service  and  report  on  such  phases  of  the  hook-worm  problem  as 
may  seem  advisable. 

270.  Diagrams  of  the  life  histories  of  various  parasitic  worms 
may  be  made  by  students.  These  mav  be  put  in  the  notebooks  or 
on  the  board.  Each  diagram  should  be  accompanied  by  a  descrip- 
tion. The  texts  by  Pearse,  Gallowav,  and  Hodge  and  Dawson  are 
good  references. 


go  PROJECTS    AND   EXPERIMENTS   IN  BIOLOGY 

36.  INSECT  PESTS 

References 

Civic  and  Economic  Biology,  Atwood,  Studies  64-67. 
Civic  Biology,  Hodge  and  Dawson,  Chaps.  X-XY. 
Economic  Zoology,  Kellogg  and  Doan. 

Elementary  Biology,  Gruenberg,  Chaps.  LXXV  and  LXXIV. 
Biology  for  Beginners,  Moon,  Chaps.  XXIII-XXV. 
Economic  Entomology,  Lochhead,  P.  Blakiston's  Son  &  Co. 
Entomology,  Folsom,  P.  Blakiston's  Son  &  Co. 
Elementary  Entomology,  Sanderson  and  Jackson,  Ginn  &  Co. 
Injurious  Insects,  O'Kane,  Macmillan  &  Co. 

271.  Excursion. — If  there  is  a  greenhouse  near  the  school,  it 
may  be  profitable  to  make  a  trip  to  it  to  study  their  methods  of 
controlling  insect  pests. 

272.  Exhibits. — The  museum  committee  should  place  on  exhibit 
such  injurious  insects  as  are  in  its  possession.  Write  out  a  legend 
for  each  exhibit  stating  something  of  the  life  history,  damage  done, 
and  methods  of  control. 

273.  Survey. — Let  each  student  be  on  the  watch  for  insects  as 
they  appear  this  spring.  Capture  them  and  bring  them  to  the  class. 
Recognize  them  as  beetles,  flies,  butterflies,  etc.  and  try  to  learn 
their  individual  names  and  what  they  live  on.  Keep  a  record  of 
the  earliest  appearance  of  insects  common  to  your  community  and 
file  the  record  with  the  archives  committee. 

274.  Topics  and  Reports. — Let  each  student  prepare  a  paper  on 
some  harmful  insect.  Make  a  chart  to  go  with  the  paper  if  you  can. 
For  an  idea  as  to  how  to  make  such  a  chart,  see  Figs.  315,324,326,  and 
335  in  Atwood's  Biology  and  similar  figures  in  the  other  references. 

275.  Tables. — Prepare  a  table  of  the  sprays  which  are  used  as 
stomach  poisons  and  state  in  the  table  what  kinds  of  insects  are 
fought  with  each  spray. 

Make  a  similar  table  for  sprays  which  are  contact  poisons. 
Make  another  table  of  stomach  poisons  which  are  not  applied 
through  a  spraying  nozzle. 

276.  Laboratory  work  should  be  done  on  an  insect  which  has 
chewing  or  biting  mouth  parts  and  on  one  which  has  sucking  mouth 


INSECT    PESTS 


91 


parts.  See  Figs.  32,  328,  329,  and  330  in  Atwood's  Biology  and 
the  figures  of  the  grasshopper  in  Unit  6  of  this  manual.  Insects 
having  chewing  mouth  parts  which  are  easily  studied  are  caterpillars, 
grubworms,  beetles,  dragon  flies,  and  grasshoppers.  [nse<  1-  having 
piercing  and  sucking  mouth  parts  which  may  be  studied  arc  squash 
bugs,  assassin  bugs,  electric  light  bugs,  cicadas,  and  some  of  the  flii 
After  carefully  consulting  the  figures  in  reference  books,  each  student 


I    li  h 


Fig.  53. 


Fig.  54. 


Fig.  53. — Mouth  parts  of  the  mosquito  to  show  a  type  of  piercing  mouth 
parts,  a,  Antenna;  e,  compound  eye;  h,  hypopharynx;  /,  labrum-epiphary  nx ; 
li,  labium;  m,  mandible;  tnx,  maxilla;  />,  maxillary  palpus.  [From  Folsom,  after 
Dimmock.) 

Fig.  54. — The  head  of  the  housefly.     {From  limns.) 

should  make  a  study,  with  the  aid  of  a  lens,  of  the  mouth  parts  of  a 
chewing  and  a  sucking  insect.  Make  sketches  of  the  mouth  parts 
and  label  them  carefully.  Do  you  understand  why  stomach  poisons 
do  not  kill  bugs?  If  bugs  do  not  eat  the  leaves  of  a  plant,  how  do 
they  do  it  damage?     Which  is  the  more  primitive  type  of  mouth? 


92  PROJECTS    AND   EXPERIMENTS    IN  BIOLOGY 

In  examining  mouth  parts  of  insects,  the  student  should  use  a  fine  tweezers 
and  a  needle  point.  Those  of  the  chewing  insects  may  be  removed  and  sketched 
apart  from  the  head  or  they  may  be  left  on.  It  will  be  best  to  leave  the  mouth 
parts  of  sucking  insects  on  the  head  and  sketch  them  in  that  way.  They  should 
he  separated  for  observation  with  great  care  or  they  will  be  broken.  The  needle 
point  is  best  for  this  purpose.  Thrust  it  between  them  near  the  head  and  gently 
work  it  down  to  the  point  of  the  beak  parting  the  mouth  parts  as  you  do  so. 

277.  Exhibit. — The  supplies  committee  should  make  an  exhibit 
of  the  various  chemicals  which  are  used  in  fighting  insects.  They 
may  be  put  in  glass  bottles  and  set  out  for  observation  with  such 
notes  as  may  seem  appropriate.  Caution. — Some  of  the  chemicals 
are  very  poisonous. 

278.  Review. — If  the  grasshopper  was  dissected  in  a  previous 
study,  it  should  be  reviewed  now;  but  if  not,  it  will  be  well  to  turn 
to  the  directions  there  and  make  a  careful  study  of  the  structure  of 
the  grasshopper  considered  as  a  typical  insect. 

279.  News  Item. — Flies  are  being  bred  in  our  city  at  the  rate  of  one  million 
every  twenty-four  hours.  The  committee  on  civic  surveys  of  the  biology  class 
of  the  high  school  reports  finding  a  manure  heap  on  River  Avenue  which  is  pro- 
ducing a  million  flies  every  day.  We  wonder  if  all  of  the  citizens  of  Blank  have 
been  getting  their  share  of  these  flies.  A  statistician  on  the  committee  reports 
that  there  are  104  flies  for  each  family  in  the  city,  and  several  times  that  figure 
for  each  grocery  store  per  day. 

We  hasten  to  inform  the  curious  that  it  will  be  necessary  to  start  at  once  if  they 
desire  to  see  this  marvel  of  insect  breeding,  for  the  manure  is  being  removed 
today.  We  regret  to  announce  the  destruction  of  so  beautiful  a  fly  paradise,  but 
the  school  physician  held  a  conference  with  its  owner  with  the  result  that  it  was 
sold  for  fertilizer  at  a  satisfactory  profit. 

The  above  news  item  is  a  gem  of  biological  literature.  It  con- 
demns no  one,  is  somewhat  humorous,  and  lets  those  who  have 
manure  piles  know  indirectly  that  they  must  be  removed.  There 
should  be  considerable  manure  for  sale  the  day  following  the  publica- 
tion of  such  an  article.  Is  it  necessary  to  publish  such  an  article  in 
the  press  of  your  city?  When  the  fly  season  opens,  there  should  be 
no  manure  piles.  Such  piles  do  little  harm  in  the  winter,  but  when 
spring  comes  the  flies  which  have  wintered  over  in  them  in  the  form 
of  maggots  and  pupae  begin  to  come  out,  and  other  flies  lay  their 
eggs  there.     Appoint  a  committee  to  make  a  survey. 


INSECT    PESTS  93 

280.  Fly  Breeding  Project.— Secure  some  fly  eggs  or  young  larvae 
and  some  manure.  Place  them  in  a  glass  jar  and  observe  their 
development  from  day  to  day.  I  Mace  them  in  the  care  of  some 
student  who  will  see  that  the  culture  is  kept  properly  until  the 
flies  develop.  Keep  a  record  of  the  length  of  the  stages  of 
development.  Does  food  or  temperature  affect  the  length  of  the 
stages? 

281.  Laboratory  Study. — With  the  aid  of  a  lens  and  the  compound 
microscope  the  fly  should  be  carefully  examined.  Dip  each  fly  in  a 
solution  of  formalin  before  handling  it  to  kill  any  germs  which  may 
be  on  it.  The  wings  are  gauzy  and  covered  with  hairs.  Note  the 
veins  which  keep  them  stiff.  The  head  is  possessed  of  two  large 
compound  eyes.  Find  the  bristle-like  antennae.  The  mouth  parts 
are  adapted  for  lapping  up  fluids.  Can  you  identify  the  mandibles, 
maxillae,  and  labium?  The  body  is  divided  into  a  head,  thorax, 
and  abdomen.  The  thorax  is  composed  of  three  fused  somites. 
Each  somite  bears  a  leg.  Note  the  hairs  on  the  legs.  Are  they 
well  adapted  to  carrying  bacteria?  Place  a  fly's  foot  under  the 
compound  microscope  and  view  it.  Find  the  two  hooks,  the  pad, 
and  note  the  hairs.  The  abdomen  is  composed  of  somites  which  are 
easily  distinguished.  How  many  are  there?  Note  the  hairs.  Is 
the  fly  a  good  carrier  of  germs?  If  time  permits,  sketches  of  vari- 
ous parts  of  the  fly  may  be  made. 

283.  Fly  Trap  Exhibit. — A  committee  may  be  appointed  to  secure 
some  fly  traps,  or  they  may  be  made.  Exhibit  them  to  the  class. 
See  Hodge  and  Dawson's  Biology,  Chap.  X. 

284.  Fly  poison  may  be  made  by  placing  a  little  sugar  or  honey 
in  a  saucer  of  water  and  adding  a  small  amount  of  formalin.  It  may 
be  well  to  place  a  slip  of  paper  in  the  dish  for  the  flies  to  light  on. 
All  water  must  be  removed  from  the  room.  Flies  require  large 
quantities  of  water  and  are  fond  of  water  containing  a  little 
formalin.  If  there  are  flies  in  the  laboratory,  this  experiment  may 
be  tried;  but  there  must  be  no  water  for  them  to  get  at,  other  than 
the  poison. 

285.  Arachnids.  -Examine  specimens  of  spiders,  centipeds,  and 
millipeds  and  make  out  the  tables  on  pp.  424  and  432  of  Atwood's 
Biology. 


94  PROJECTS   AND   EXPERIMENTS    IN  BIOLOGY 

286.  Reports  may  be  given  on  the  life  histories  and  methods  of 
control  of  various  arachnid  pests.  Government  bulletins  will  be 
found  to  be  the  best  references. 

287.  Spider  webs  may  be  studied  as  projects.  How  are  they 
made?  What  are  they  used  for?  How  many  kinds  are  there?  A 
few  minutes  of  the  recitation  hour  may  be  devoted  to  an  exchange  of 
information  and  ideas  on  spider  webs. 


37.  RATS  AND  MICE 

References 

Civic  and  Economic  Biology,  Atwood,  Study  68. 
Civic  Biology,  Hodge  and  Dawson,  Chap.  XVII. 
Bulletins  of  the  U.  S.  Department  of  Agriculture. 

288.  David  Lantz  estimates  that  a  rat  does  two  dollars  worth 
of  damage  every  year  of  its  life.  How  much  wheat  would  it  eat  to 
amount  to  this  figure?     Corn?     Flour? 

Each  student  will  make  a  list  of  the  ways  in  which  rats  have  been 
known  personally  to  destroy  property.  Bring  the  lists  to  class. 
Compare  and  average  them.  It  may  be  well  to  collect  the  averages 
in  a  table. 

289.  Bubonic  Plague. — Consult  references  and  make  a  diagram  of 
the  life  history  of  bubonic  plague. 

290.  Survey. — A  survey  committee  should  collect  some  infor- 
mation on  the  rat  problem  in  your  city.  Where  are  they  the  most 
abundant?  Are  there  any  open  sewers?  Can  a  movement  be 
started  and  carried  out  to  have  the  sewers  covered?  Are  there  any 
garbage  dumps  in  the  city?  Is  it  possible  to  have  the  garbage 
burned?  Are  any  of  the  merchants  or  manufacturers  suffering  loss 
by  rats?  In  making  surveys,  you  should  always  be  courteous  and 
diplomatic. 

291.  Problem. — If  a  rat  brings  forth  ten  young  to  a  litter,  and 
breeds  four  times  in  a  year,  how  many  rats  will  there  be  at  the  end 
of  five  years? 


FISH   AND    POND    LIFE  95 


38.  FISH  AND  POND  LIFE 

References 

Fish  Culture  in  Ponds  and  other  Waters,  Meehan,  Macmillan  &  Co. 

Civic  and  Economic  Biology,  Atwood,  Study  69. 

Civic  Biology,  Hodge  and  Dawson,  Chap.  XXVI I. 

Biology  for  Beginners,  Moon,  Chap.  XX VII. 

General  Zoology,  Pearse,  Henry  Holt  &  Co. 

Life  of  Inland  Waters,  Xeedham  and  Lloyd,  Comstock  Pub.  Co. 

292.  Excursion. — If  there  is  a  pond,  lake,  or  stream  in  the 
vicinity,  an  excursion  should  be  made  to  it.  Dip  nets,  glass  jars, 
pails,  etc.  should  be  taken  along.  What  animals  do  you  find  in 
the  water?  Is  the  water  clear,  running,  muddy,  or  stagnant?  What 
is  the  condition  of  the  bottom?  What  is  the  source  of  supply  of 
the  body  of  water  which  you  are  visiting? 

What  kinds  of  insects  are  present?  What  kinds  of  molluscs? 
What  kinds  of  plants?     What  kinds  of  crustaceans?    List  them. 

Catch  as  many  of  the  animals  which  live  in  the  pond  as  you  can. 
Place  them  in  aquaria  in  the  laboratory  and  study  them.  What 
ones  are  eaten  by  fish?  Which  ones  eat  others?  What  is  the  source 
of  all  food  in  water? 

Make  a  list  of  the  fishes  which  are  known  to  inhabit  the  body  of 
water.  Do  you  know  what  each  feeds  on?  W7hat  might  be  done  to 
increase  the  number  of  fish  which  could  be  taken  from  the  pond  each 
year? 

Discuss  the  questions  raised  above  when  you  meet  in  class  the 
next  day. 

293.  Aquaria. — Review  the  work  done  with  aquaria  last  fall. 
Are  any  of  the  aquaria  in  the  same  condition  in  which  they  were 
left  last  fall?  What  changes  have  taken  place?  Review  the  chemi- 
cal cycles  in  ponds  and  aquaria.  Understand  the  relationships  of 
plants  and  animals  in  water.  What  kinds  of  fish  have  you  been 
able  to  keep  in  the  laboratory? 


96  PROJECTS    AND    EXPERIMENTS    IN  BIOLOGY 

39.  THE  PERCH  (DISSECTION) 

References 

Comparative  Vertebrate  Dissection,  At  wood,  P.  Blakiston's  Son  &  Co. 
Laboratory  Directions  in  Elementary  Zoology,  Guyer,  U.  of  Wis.  Press. 
General  Zoology,  Linville  and  kelley,  Ginn  &  Co. 
Civic  and  Economic  Biology,  At  wood,  Study  69. 

294.  Study  a  Live  Fish  in  Water. — How  does  it  pass  water  over 
the  gills?  How  does  it  swim?  Are  all  of  the  fins  used?  Note  the 
tins.  The  one  at  the  tail  is  the  caudal.  Those  along  the  back  are 
t  he  dorsal  fins.  Those  under  the  tail  are  the  anal  fins.  Those  which 
arc  paired  are  the  pectoral  fins  near  the  head,  and  the  pelvic  fins 
along  the  sides  of  the  body  farther  back. 

Find  the  nostrils.  What  are  they  used  for?  Find  the  eyes. 
Are  they  movable?     Feed  the  fish.     How  do  they  find  the  food? 

Study  the  scales.  How  are  they  arranged?  Are  they  all  of  the 
same  size?  Note  how  they  lap  over  the  ones  behind  them.  Find 
the  lateral  line  which  is  a  line  from  above  the  eye  along  the  side  of 
the  body  to  the  tail.     It  is  a  line  of  sense  organs. 

Draw  the  fish  which  you  have  observed.  Label  all  of  its  parts 
carefully. 

295.  Dissection  of  Perch. — Specimens  with  the  ventral  wall  of  the 
body  cut  away  may  be  kept  in  formalin  from  year  to  year  and  used 
in  this  study  for  examination,  or  fresh  specimens  may  be  dissected. 
Make  a  cut  along  the  mid-line  of  the  body  and  carry  it  forward  to 
the  pectoral  girdle  and  back  to  the  anus.  Now  cut  away  the  sides 
oi  the  abdominal  walls.  This  exposes  the  visceral  organs  of  the 
perch.  Push  a  probe  into  the  mouth  and  find  where  it  enters  the 
stomach.  Note  the  shape  of  this  organ.  Find  the  pyloric  appen- 
dages at  the  place  where  the  stomach  and  intestine  meet.  How 
many  are  there?  What  is  their  function?  The  liver  is  the  dark  red 
organ  forward  from  the  stomach.  How  many  lobes  has  it?  Can 
you  find  the  green  gall  bladder?  Trace  the  coiled  intestine  through 
the  fat  which  surrounds  it  to  its  opening  to  the  outside.  How 
many  coils  are  there?  Can  you  find  the  pancreas  and  spleen? 
What  are  the  functions  of  these  organs?  The  pancreas  is  in  a 
very  simple  form  in  the  perch. 


THE    PERCH 


97 


The  reproductive  organs  are  situated  along  the  intestine  and  vary 
greatly  in  size  with  the  season  of  the  year.  Trace  their  openings 
to  the  exterior.  The  air  bladder  is  the  silvery  sac  in  the  dorsal 
part  of  the  body-cavity.  What  is  its  shape?  How  is  it  attached? 
The  kidneys  are  situated  between  the  bladder  and  the  backbone. 
They  are  of  a  dark  red-brown  color.     What  is  their  extent? 


lateralis  system' 


ophthalmic 


maxillary 
\    'mandibular 
hyomandibular 


Fig.   55. — The  brain  and  ten  cranial  nerves  of  the  perch  as  seen  from  side  view. 
{Comparative    Vertebrate  Dissection,   Atwood.) 

The  heart  is  situated  between  the  gills  in  the  thick  triangular 
area.  Cut  into  it  and  observe  the  heart.  Find  the  atrium  (auricle) 
and  the  ventricle.  It  will  be  difficult  for  a  student  of  high  school 
grade  to  make  out  the  blood  vessels  without  injection,  but  they  are 
charted  in  Figs.  98  and  99  in  Atwood's  Biology.  Understand  how 
the  blood  traverses  the  body  of  a  fish  and  compare  it  with  that 
of  man  and  the  frog. 

The  brain  and  cranial  nerves  of  the  perch  are  shown  in  the  illustra- 
tion.    Cut  away  the  roof  of  the  skull  and  remove  the  fatty  material 


98  PROJECTS     VXD    EXPERIMENTS    IX  BIOLOGY 

which  surrounds  the  brain.  The  most  anterior  lobes  comprise  the 
cerebrum,  the  second  pair  are  the  optic  lobes,  and  the  third  unpaired 
lobe  is  the  cerebellum.  Try  to  find  the  cranial  nerves  which  are 
shown  in  the  illustration.     You  may  not  be  able  to  find  them  all. 

The  muscles  of  the  perch  are  of  the  segmented  type  along  the 
sides  of  the  body.  They  are  an  evidence  of  the  fact  that  vertebrated 
animal-  are  segmented  as  is  the  earthworm,  but  these  evidences  are 
much  less  evident  in  the  higher  forms.  Strip  a  piece  of  skin  from 
the  side  of  the  body  and  tail  and  observe  the  muscles.  For  refer- 
ences on  the  anatomy  of  the  perch  consult  Comparative  Vertebrate 
Dissection,  Atwood,  P.  Blakiston's  Son  &  Co.  and  General  Zoology, 
Linville  and  Kelly,  Ginn  &  Co. 

Draw  such  parts  of  the  anatomy  of  the  perch  as  your  instructor 
may  direct. 

40.  BIRDS 

References 

Civic  and  Economic  Biology,  Atwood,  Study  70. 
alimentary  Biology,  Gruenberg,  Chap.  LXXVII. 
Civic  Biology,  Hodge  and  Dawson,  Chaps.  IV  and  V. 
.Y<  w  Essentials  of  Biology,  Hunter,  pp.  286-302. 
Biology  for  Beginners,  Moon,  Chaps.  XXXI  and  XXXIT. 
Bird  Xeighbors,  Blanchan,  Doubleday  Page  &  Co. 

296.  Laboratory  Work. — The  following  study  may  be  made  from 
a  live  bird  or  from  a  mounted  specimen.  Distinguish  the  following 
regions:  head,  neck,  body,  and  tail.  The  bill  is  peculiar  to  birds. 
Does  it  contain  any  teeth?  Find  the  nostrils.  Note  their  shape 
and  position.  Are  they  covered  with  feathers?  Find  the  eyes. 
Are  they  possessed  of  lids?  What  is  the  color  of  the  eyes?  What 
is  the  shape  of  the  pupil?  Find  the  ears.  Is  there  an  external  ear? 
How  is  the  ear  covered? 

The  neck  and  body  are  covered  with  feathers  which  are  so 
arranged  as  to  shed  the  rain  and  to  offer  as  little  resistance  to  flight  as 
possible.  How  are  the  wings  folded?  How  many  joints  are  there? 
The  long  feathers  are  firmly  set  in  the  flesh  of  the  wing.  Note  how 
they  overlap  when  the  wing  is  spread.  Examine  a  large  feather. 
The  part  which  was  in  the  flesh  is  the  quill.     The  stiff  central  portion 


BIRDS  99 

is  the  rachis.  The  barbs  run  out  from  the  rachis  and  possess 
barbules  which  lock  them  together. 

How  many  joints  are  there  in  the  legs?  How  much  of  the  leg 
is  covered  with  feathers?  Note  how  the  scales  are  arranged.  How 
many  toes  are  there?  On  what  part  of  the  foot  does  the  bird  walk? 
Are  the  feet  webbed?     What  are  the  toe  nails  fitted  for? 

The  tail  of  a  bird  is  short,  but  it  may  contain  long  feathers.  Com- 
pare them  with  those  of  the  wings.  Is  the  tail  broad  or  pointed. 
What  are  the  uses  of  birds'  tails? 

Draw  a  bird  from  side  view  in  outline  and  label  its  parts. 

297.  Migration  Chart. — Make  a  tabulation  of  the  dates  of  arrival 
of  the  migratory  birds  which  pass  through  your  section  of  the 
country.  Let  each  student  be  on  the  watch  for  birds  and  record 
those  which  he  sees.  Post  the  list  in  the  school  and  compare  lists 
from  year  to  year. 

298.  Field  Study. — Go  into  the  woods  and  fields  on  Saturday  in 
groups  of  less  than  ten.  If  there  are  too  many  in  a  group,  the  birds 
will  be  frightened  away.  Have  notebooks  with  you  and  record  the 
names  of  the  birds  which  you  see.  These  trips  should  be  started 
before  the  leaves  come  out,  because  the  birds  are  more  easily  seen 
then.  When  the  birds  begin  to  build  their  nests,  the  process  of 
nest  building  should  be  observed.  In  what  situation  does  each 
bird  build?  What  materials  go  into  the  nest?  How  are  thev  fast- 
ened together?  Do  both  birds  assist  in  building?  When  are  the 
eggs  laid?  What  is  their  color?  Do  both  birds  incubate  them? 
What  are  the  young  like?  Do  both  birds  feed  them?  What  do  they 
feed  them?  A  blind  may  be  made  and  a  watcher  placed  in  it  to 
make  a  daily  record  of  the  food  given  to  the  nestlings.  The 
watcher  should  be  relieved  every  hour.  Are  the  birds  which  you 
have  watched  beneficial?  Do  owls  hunt  all  night?  It  will  not  be 
necessary  to  watch  the  song  birds  after  dark. 

Aside  from  nest  building  the  songs  and  colors  of  birds  are  the  most 
interesting.  Learn  to  know  them  by  their  colors  and  songs.  Note 
differences  in  males  and  females.  What  differences  may  be  noted  in 
young  and  old  birds?  It  is  difficult  to  see  the  color  of  a  bird  when  it 
is  between  you  and  the  sun,  or  when  it  is  in  the  bright  light.  Colors 
show  best  in  quiet  woods. 


IOO  PROJECTS   AND   EXPERIMENTS   IN  BIOLOGY 

Watch  a  sparrow's  nest  while  the  young  are  being  feed.  You 
may  be  surprised  at  the  large  number  of  insects  which  are  fed  to  the 
young.     Sparrows  do  much  good  and  some  harm. 

299.  Bird  Calendar. — List  all  of  the  birds  of  the  community  as 
summer  residents,  winter  residents,  permanent  residents,  and 
migrants.  Give  the  dates  of  arrival  and  departure.  This  calendar 
should  be  started  by  the  first  class  and  corrected  and  amplified 
from  year  to  year.  It  should  be  placed  in  charge  of  the  archives 
committee. 

300.  Survey. — A  tabulation  may  be  made  of  the  shrubs  in  the 
community  which  bear  fruits  which  are  eaten  by  birds.  What 
can  be  done  to  increase  the  number  of  such  shrubs?  Will  this  have 
a  tendency  to  increase  the  number  of  birds  in  the  community? 

301.  Bird  Boxes. — Arrange  with  the  manual  training  department 
to  make  some  bird  boxes.  Have  an  exhibit  of  them.  When  they 
are  set  up,  they  should  be  put  out  of  the  way  of  cats. 


•  . 


- 


INDEX 


Absorption,  39 

Acid  secretion,  14 

Adaptation,  4 

Aerial  roots,  14 

Ailanthus,  59 

Air,  5 

Albinos,  74 

Alcohol,  26,  84 

Alfalfa,  30 

Algae,  47-49 

Alkali,  38 

Alligator,  68 

Ameba,  45 

Ammonium  nitrate,  2 

Andalusian  fowls,  74 

Animal  intelligence,  45 

Antidiphtheric  serum,  84 

Apparatus,  1 

Apple  56,  60,  74,  79 

Apt  era,  10 

Aquaria,  29,  46,  86,  95 

Arachnids,  93 

Arborvitae,  24 

Archives,  1 

A  ristolochia,  20-2 1 

Ascaris,  89 

Avoiding  reaction,  46 

Babcock  test,  36,  75 
Bacteria,  28,  79-86 
Balanced  aquarium,  46 
Banteng,  75 
Barberry,  88 
Barley,  35 
Bean,  63 
Bears,  29 
Bees,  6 
Beet,  14,  16 
Beetle,  3,  6 


Begonia,  60 
Berries,  57 
Bird  boxes,  100 

calendar,  100 
Birds,  57,  66,  78,  98-100 
Biuret  test,  35 
Blood,  40 

corpuscles,  40 
Brace  roots,  14 
Brain  of  frog,  44,  70,  71 

of  perch,  97,  98 
Bread  mold,  79,  81 
Brook,  4 
Bryophyllum,  60 
Bubonic  plague,  94 
Buds,  18-23 
Bulbs,  19,  60 
B urban k,  75 
Butter,  35 
Butterflies,  6 

Calendars,  51 
Calories,  29 
Camel,  78 
Cancer,  85 
Candy,  35 
Capillarity,  17 
Carbohydrate,  2,  24 
Carbon  cycle,  29 

dioxide,  26,  27  28,  29,  39 

monoxide,  39 

test,  32 
Carrot,  14 

osmometer,  16 
Cats,  100 
Cell,  52-53 

budding,  5  j 

division,  52-53 

growth,  5a 


101 


102 


INDEX 


Cellj  turgor,  16 
Centipeds,  93 
Chemical  compound,  2 

cycles,  29 
Cherry,  19,  57 
Chicken  3,  66,  79 
Chlorophyll,  26,  28,  48 
Chloroplasts,  27,  47 
Chromosomes,  53,  74 
Cider,  84 

Circulation,  39-41,  68 
Clay,  17 
Cleavage,  65 
Clematis,  59 
Clover,  88 
Conjugation,  47 
Committee,  1 
Compass  plant,  4 
Cones  of  pines,  50 
Contact  poisons,  90 
Contagious  diseases,  84-87 
Copper  oxide,  34 

sulphate,  2 
Corms,  19,  60 
Corn,  18,  62,  63,  64,  65,  73,  74,  94 

judging,  75 

oil,  39 

s,talk,  23 

testing,  75 
Cotton,  18,  35 
Cottonseed  oil,  39 
Cottonwood,  60 
Cow,  3 

Crawfish,  10-14 
Crayfish,  10-14 
Crop  rotation,  18 
Crustaceans,  44 
Crystallization,  2 
Culture  medium,  80 

Dahlia,  60 
Diastase,  34 
Diaphragm,  40 
Diffusion,  25,  26 


Digestion,  36-39 
Digestive  juices,  38 

system,  36,  37,  38 
Diptera,  10 
Ditch  moss,  26 
Dog,  3,  29,  45,  79 
Domesticated  animals,  72-73 

plants,  72-73 
Dough,  83 
Dove,  79 
Drainage,  18 
Duck,  3 

Eugenics,  76-78 
Eagle,  78 
Ear,  13,  44 
Earthworm,  4,  40,  42 
Eggs,  65,  69 
Element,  2 
Elephant,  3,  78 
Elm,  59 
Elodea,  26,  27 
Embryos,  66 
Emulsion,  39 
Energy  of  exercise,  41 
English  ivy,  21 
Environment,  4 
Ephemerida,  10 
Euglena,  28 
Euthenics,  76-78 
Evolution,  78-79 

Excursions,  4,  5,  18,  49,  77,  78,  83,  88, 
9°>  95>  99 

Fascicled  roots,  14 
Fat,  2,  39 

tests,  35 
Feeble-mindedness,  77 
Fehling's  solution,  34,  38 
Fennel,  88 
Fern,  25,  47-49 
Fermentation  tube,  83 
Ferric  chloride,  36 
Fibrous  roots,  14 


INDEX 


I03 


Field  trips,  4,  5,  18,  49,  77,  78,  83,  88, 

90,  95,  99 
Fire,  41 
Fish,  65,  95 

Flies,  3,  6,  78,  91,  92,  93 
Fly  larvae,  93 

poison,  93 

traps,  93 
Flour,  35 

Flower  calendar,  51 
Flowering  plants,  53-55 
Flowers  5,  50-51 
Food,  5,  28-36,  64 

cycle,  29 

tests,  32 
Forestry,  21 
Formaldehyde  test,  36 
Formalin,  80 
Fossils,  78 
Fox,  75 
Fungi,  83 
Furs,  75 

Frog,  36,  41,  43,  65,  67-72 
Fruits,  55-59 

Game  laws,  75 

Geotropism,  41,  64 

Geranium,  26,  60 

Gleocapsa,  47 

Glucose,  2,  28,  34,  35,  38,  39,  65,  83 

tests,  34 
Glue,  2,  35 
Goldenrod,  5-6 
Goldfish,  86 
Grafting,  60-61 
Grass,  5 

Grasshopper,  6-10,  92 
Growth  3,  52 
Guinea  pigs,  74 
Guttation,  26 

Hay  infusion,  45 
Heart,  40,  68,  97 
Heat  test,  34 


Heliotropism,  42 
Hemipicra,  10 
Hemlock,  24 
Heredity,  53,  73~75 
Honey,  39,  83 
Hook-worm,  89 
Horse,  78 
Human  eye,  44 
Humus,  17 
Hybrids,  74 

Hydrochloric  acid,  36,  38 
Hydrotropism,  42,  64 
Hygroscopic  water,  17 
Hymenoptera,  10 

Ice  cream,  35 
Images,  44 
Inflorescence,  51 
Inheritance  chart,  76,  77 
Inherited  defects,  76,  77 
Insectivorous  plants,  31 
Insect  mouth  parts,  90 
Insect  pests,  90-94 
Insects,  6,  40,  44,  90-94 
Iodine,  32 
Iron,  26 
Irritability,  2,  3 

Jimson  weed,  88 
Juniper,  24 

Law  of  chance,  74 

Leaves,  5,  23-28,  49,  5°,  60 

blue  prints  of,  26 

of  conifers,  25 

of  pines,  50 

palmate,  23 

pinnate,  23 
Lepidoptera,  10 
Library,  1 
Light,  5 

Lilac  mildew,  87 
Lilies,  24,  53 
Limestone,  17,  26 


104 


INDEX 


Limewater,  35,  41,  84 

Linden,  59 
Litmus,  16,  35 
Live-for-ever,  24,  60 
Lumber,  50 
Lungs,  41 
Lung  capacity,  41 
Lymphatic  system,  38 

Malaria,  84,  86 
Mammal,  66,  78 
Man,  3,  37 
Manure,  30 
M;iple,  59 
Matter,  2 
Meadow,  4 
Mendel,  74 
Mice,  74,  94 
Migration  chart,  99 
Milk,  35 

tests,  35-36 
Millipeds,  93 
Millon's  test,  35 
Mimosa,  3,  42 
Mineral  matter,  35 
Minerals,  2 
Mitosis,  52 
Mosquito,  85,  91 
Moisture  test,  35 
Molds,  28,  60,  79-84 
Mosses,  47-49 
Mucilage,  35 
Mulch,  17 
Mushrooms,  83 
Muskrat,  75 

Nectar,  50 
Nerve  cell,  43 
Nervous  impulse,  43,  44 
Nitrogen,  18,  29,  30 
cycle,  29,  30 

Odonata,  10 
Oil  tests,  35 


Onion,  24,  53 
Orthoptera,  10 
Osmosis,  16,  39 
Overproduction,  78 
Oxygen,  26,  27,  39 

Pancreatin,  39 
Paramecia,  43,  45 
Parasitic  worms,  89 
Park,  18 
Pea  seed,  63 
Pendulum,  44 
Pepsin,  38 
Perch,  96-98 
Percolation,  17 
Perfume,  50 
Personal  survey,  86 
Petri  dishes,  82 
Photosynthesis,  24,28 
Phototropism,  42,  64 
Pigeon,  66 
Pine  tree,  23,  49-50 
Pitcher-plant,  31 
Plane  sawed  oak,  21 
Plant  diseases,  87 

propagation,  60-62 
Plasmodium  malaria,  47 
Plate  gardens,  15 
Pleurococcus,  47,  48,  52 
Pneumonia,  84 
Pumpkin,  16,  84 
Pure  cultures,  82 
Poison  hemlock,  88 

ivy,  88 

oak,  88 

sumach,  88 
Pollen,  51 

grains,  54,  55 
Pollination,  51 
Pond,  4 

life,  95 
Potassium  chlorate,  2 

dichromate,  2 

iodide,  32 


INDEX 


I05 


Potassium  sulphate,  2 
Potato,  3,  18,  60 
Protein,  2 

tests,  34 
Protozoans,  45-47 

Quarter  sawed  oak,  21 
Quetlet's  law,  74 

Raspberry,  58 

Rats,  74,  94 

Reason,  45 

Respiration,  68,  39-41 

Responses,  41-45 

Rhizomes,  19,  60 

Robin,  3 

Rochelle  salt,  34 

Rocks,  17 

Root  hairs,  14,  16,  17 

Roots,  3,  6,  14,  17,  18,  27,  60,  63 

Saliva,  34 

Salivary  digestion,  38 

Salt,  2,  35,  43,  64,  79 

Sand, 17 

Sanitation,  1 

Sap,  20,  27 

Seed  germination,  62-65 

Seedlings,  27,  62-65 

Seeds,  60,  62-65 

Sensitive  plant,  3,  42 

Sewers,  94 

Sheep,  3 

Shelter,  5 

Shrubs,  77,  100 

Silver  nitrate,  2 

Sirup,  83 

Skeleton  leaves,  26 

Skeletons,  78 

Skunk,  75 

Smallpox,  84 

Snake,  3 

Soaps,  39 

Soda,  35 


Sodium  bromide,  2 

chloride,  2 

hydroxide,  27,  34 

iodide,  2 
Soil,  5,  14 
Sonometer,  44 
Soudan  III,  35 
Sour  milk,  35 
Sparrow's  nest,  100 
Spiders,  93 
Spider  webs,  94 
Spirogyra,  48,  52 
Spores,  60 
Sprays,  90 
Spruce,  23 
Squashes,  16,  74 
Squash  seed,  63 
Starch,  2,  27,  32,  35,  39 

grains,  32,  33 

iodide,  32 

tests,  32 
Stem,  5,  18-23,  60 
Stomach,  38 
Stomach  poisons,  90 
Stomates,  24 
Strawberry,  58 
Sugar,  2,  16,35,55,  79,83,84 
Sundew, 31 
Sunlight,  2,  5,  28 

Tadpole,  66 
Tapeworm,  89 
Tap  roots,  14 
Teeth,  38,  84 
Temperature,  5 
Thermometer,  41 
Thermotropism,  43 
Thigmotropism,  42 
Tomatoes,  S4 
Tracheal  system,  40 
Transpiration,  24,  25 
Trap  nests,  75 
Tree  calendar,  51 
Trees,  18,  21 


PROPERTY  i/v 

1 06  N.  C  State  C 

Tree  stumps,  22 
Trial  and  error,  43 
Trichina,  89 
Tropisms,  41-45 
Tuberculosis,  84 
Tubers,  19,  60 
Tulips,  20,  24 
Turtle,  3,  66 
Typhoid  fever,  84 

Ulothrix,  48 

* 

Vaccination,  84 
Variation,  73-75 
Vaucheria,  48 
Ventilation,  1 
Venus  fly-traps,  31 
Vestiges,  78 
Vinegar,  79,  84 


INDEX 


Walking  fern,  60 
Water,  5 

test,  ss 
Weeds,  4,  14,  78,  88-89 
Weed  seed,  88 
Wheat,  35,  74,  94 
White  pine,  22 
Wild  animals,  75 
Willow,  21,  60 
Wood,  50 
Woods,  4,  18 
Wool,  35 
Worms,  89 

Xanthoproteic  test,  34 

Yeast,  28,  79-84 
Yellow  fever;  84 

Zebu  cattle,  75 


871  B5« 

K/01/00  41245 


10 


St  if 


s 


I 


V 


